A panel builder usually does not make an SMPS selection by asking only, "How many watts do I need?"

The actual question is more practical.

What voltage do the PLC, sensors, relays and transmitters require? How much current will they draw together? Are there solenoid valves or other loads that create a higher starting demand? How much spare capacity should remain for future additions? And will the power supply physically fit into the available DIN rail space without creating a heat problem?

This is where many control panel designs go wrong.

A 24 V DC SMPS may look like a simple component compared with a PLC or HMI, but almost every DC powered device in the panel can depend on it. If the supply is undersized, unstable or poorly matched to the load, several devices may start behaving incorrectly at the same time.

Radical TechMart's current Multispan Power Supplies category includes 5 V, 12 V, 15 V and 24 V DC SMPS options, including PS5, PS12, PS15, PS24 and PSW series products.

The right Multispan SMPS for an industrial control panel therefore starts with understanding the load, not simply choosing the largest available model.

What Does an SMPS Do Inside a Control Panel?

SMPS stands for Switch Mode Power Supply.

In a typical industrial control panel, the incoming supply may be AC while many automation devices require regulated low voltage DC.

The SMPS converts the available input power into the DC voltage required by equipment such as:

In simple terms, the SMPS becomes the DC power source for the control side of the panel.

That makes its selection more important than its physical size suggests.

Start With Output Voltage, Not Current

Before calculating amperes or watts, identify the required DC voltage.

The current Multispan range listed by Radical TechMart includes several voltage families:

These families are currently shown in Radical TechMart's Multispan Power Supplies collection.

For most automation panels, 24 V DC is a common control voltage, but that does not mean every device in every project operates at 24 V.

Always check the actual equipment.

A communication module may require 5 V. Another system may contain 12 V devices. Certain electronics may require 15 V.

Do not choose the SMPS voltage based on habit.

Choose it based on the load.

Calculate the Real Panel Current

Once the voltage is known, list every device that will be powered by that SMPS.

For example, consider a 24 V DC panel containing:

This does not automatically mean you should select a 3.5 A supply.

Operating continuously at the absolute limit leaves little tolerance for additional loads, startup demand, future panel modifications or variations in actual consumption.

A practical panel design should therefore include reasonable spare capacity rather than sizing the SMPS exactly at the calculated steady load.

The exact margin depends on the connected equipment and application, so use the equipment manufacturers' current consumption figures rather than relying on generic assumptions.

Why Selecting Only by Wattage Can Be Misleading

Power is calculated from voltage and current.

For a DC supply:

Power = Voltage × Current

A 24 V, 5 A supply corresponds to 120 W of DC output capacity.

A 12 V, 5 A supply corresponds to 60 W.

Both are "5 amp" supplies, but they are not interchangeable.

This is why voltage, current and wattage must be considered together.

The current Multispan PS24 listing includes versions from 24 V DC, 1 A up to 10 A, representing a broad range of power capacities for different panel loads.

The PS12 family similarly covers 12 V loads from 1 A to 8 A, with listed variants from 12 W to 96 W.

Where the Multispan PS24 Series Fits

For a conventional industrial automation panel using a 24 V DC control system, the PS24 family is a logical range to evaluate.

Radical TechMart currently lists PS24 variants including 1 A, 2.5 A, 5 A, 6.5 A and 10 A class options, depending on the listed model.

Best for: PLC panels, automation panels, OEM machines and other systems built around 24 V DC control power.

Why this series makes sense: The current range allows the panel designer to choose the supply according to actual load instead of installing one oversized SMPS in every panel.

The listing also identifies overload, short circuit, overvoltage and overtemperature protection functions, plus natural convection cooling and DIN rail or panel installation depending on the variant.

Selection caution: Do not assume every PS24 variant has identical mechanical construction, input range or other specifications. Confirm the exact model datasheet before freezing the BOM.

When the PSW Series Makes Sense

The PSW series currently includes both 12 V and 24 V DC options.

Listed versions include 24 V at 3 A, 5 A and 6.5 A, plus a 12 V 5 A version. The product page identifies DIN rail mounting, natural convection cooling and protection against overload, short circuit, overvoltage and overtemperature.

Best for: Industrial machines and control panels where a DIN rail supply with moderate 12 V or 24 V load capacity is required.

Why this series makes sense: It provides several commonly useful control panel output combinations in one product family.

Selection caution: Decide whether the application actually needs 12 V or 24 V before comparing current capacities. A PSW12 and PSW24 model solve different electrical requirements even if their enclosure looks similar.

When to Consider PS12, PS15 or PS5

Not every industrial panel is entirely 24 V DC.

The Multispan PS12 family is available for 12 V systems, with currently listed 1 A, 2 A, 5 A and 8 A options.

The PS5-2.5A provides 5 V DC at 2.5 A for lower voltage electronics and control loads.

The PS15 family is listed for 15 V DC loads with 5 A and 8 A model options. Because the current product page contains an inconsistency around the stated wattage, verify the manufacturer's latest technical documentation before final selection.

The practical rule is straightforward:

Choose the output voltage required by the equipment. Do not adapt the equipment requirement to whichever SMPS happens to be available.

Check Input Voltage Before Finalizing the SMPS

The DC output side receives most of the attention, but the AC input side matters just as much.

The PSW listing currently specifies a wide 100 V to 270 V AC input range, while individual PS12 and PS24 variants can have model dependent input specifications.

This matters when panels are installed in locations with different mains conditions or where supply fluctuations are expected.

Before ordering, confirm:

Available AC input → selected SMPS input range → required DC output

All three must match the application.

Consider the Type of Load, Not Only Total Current

A panel drawing 3 A continuously is not necessarily equivalent to another panel drawing 3 A.

A PLC, sensor and communication module combination may create a relatively predictable electronic load.

A bank of relays or solenoid valves can create more abrupt changes in current demand.

Therefore, examine which devices are connected and whether they switch simultaneously.

This is especially important in machine automation, where several outputs may energize during one operating sequence.

If the panel has significant switched loads, use their actual manufacturer data when calculating the supply requirement.

DIN Rail Space and Heat Matter

Panel designers often calculate electrical capacity correctly but forget mechanical installation.

Before selecting an SMPS, check:

The PSW and several other Multispan supplies are presented as DIN rail friendly products for industrial panels.

Natural convection also means the enclosure arrangement should allow heat to escape rather than surrounding the supply tightly with other devices.

Built In Protection Is Not a Replacement for Panel Protection

Selected Multispan SMPS listings identify functions such as overload, short circuit, overvoltage and overtemperature protection.

These features help protect the power supply and connected system under abnormal conditions.

However, an SMPS should still be treated as part of the overall panel protection architecture.

Incoming protection, wiring protection, earthing and downstream circuit protection still need to be engineered according to the actual system.

Do not assume that an SMPS with internal protection eliminates the need for proper panel protection.

Common Mistakes to Avoid

Do This, Not That

Quick Selection Checklist

Before choosing a Multispan SMPS for an industrial control panel, confirm:

1. What AC supply is available?
2. What DC output voltage is required?
3. Which devices will the SMPS power?
4. What is the current consumption of each device?
5. What is the combined normal load?
6. Are relays, solenoids or other switched loads connected?
7. How much practical spare capacity is required?
8. What SMPS output current should be selected?
9. Does the unit fit the available DIN rail space?
10. Is adequate ventilation available?
11. What protection functions are provided?
12. Is the panel ambient temperature acceptable?
13. Are additional downstream protection circuits required?
14. Has the exact model been checked against the latest datasheet?

Specifications to Confirm Before Purchase

Final specifications should always be confirmed from the latest manufacturer datasheet.

Check the input voltage range, output voltage, rated current, output power, efficiency, ripple and noise, line and load regulation, overload protection, short circuit protection, overvoltage protection, thermal protection, cooling method, operating temperature, enclosure material, mounting type, DIN rail dimensions, terminal arrangement and required installation clearance.

Why Buy Multispan SMPS from Radical TechMart?

A request such as "24 V SMPS required" is not enough information to select a control panel power supply correctly.

A better inquiry includes the incoming supply, output voltage, total current, load type, DIN rail requirement and panel environment.

Radical TechMart currently lists Multispan SMPS families covering 5 V, 12 V, 15 V and 24 V DC requirements, with multiple current capacities for industrial and OEM applications.

The focus should be to match the power supply to the panel rather than simply choosing the highest current model available.

Final Thoughts

Choosing the right Multispan SMPS for an industrial control panel is mainly a load matching exercise.

Start with the required DC voltage.

Then calculate the real current demand.

Consider switched loads, future additions, physical panel space, ventilation and input supply conditions.

Only after these points are clear should you compare PS5, PS12, PS15, PS24 or PSW models.

The correct SMPS is not necessarily the biggest one in the catalogue. It is the supply that can power the connected control system reliably while fitting the electrical and mechanical design of the panel.

FAQs

1. What is an SMPS used for in an industrial control panel?

An SMPS converts the available input supply into regulated DC power for devices such as PLCs, sensors, transmitters, relays, controllers, HMI units and communication modules.

2. Which Multispan SMPS should I use for a 24 V PLC panel?

Start by calculating the total 24 V DC current required by the PLC and every other connected load. Multispan's current PS24 and PSW ranges include several 24 V DC current capacities. Select the model only after calculating the total load.

3. How do I calculate SMPS current for a control panel?

Add the maximum current requirements of all devices powered by the supply. Then consider the characteristics of switched loads and suitable spare capacity rather than selecting a unit that exactly equals the calculated normal load.

4. Can I use a 10 A SMPS when my panel consumes only 2 A?

Electrically, a load draws the current it requires, but using a substantially oversized power supply may increase cost, panel space and unnecessary capacity. Selection should be based on the application, future expansion and panel design.

5. What is the difference between the Multispan PS12 and PS24 series?

The main distinction is output voltage. PS12 models are intended for 12 V DC loads, while PS24 models provide 24 V DC. Each family also includes different current capacities.

6. Does Multispan offer a 5 V SMPS?

Yes. Radical TechMart currently lists the Multispan PS5-2.5A, providing 5 V DC at 2.5 A.

7. What protection should an industrial SMPS have?

Depending on the model, useful protections include overload, short circuit, overvoltage and overtemperature protection. Confirm the functions and recovery behavior from the exact model datasheet.

8. What information should I provide when requesting an SMPS quotation?

Provide the incoming voltage, required DC output voltage, total load current, connected equipment, preferred mounting style, available panel space and any important environmental or protection requirements.

A panel builder rarely has the problem of finding one instrument.

The real challenge is making twenty or fifty instruments work together across different panels without creating a maintenance problem six months later.

One machine may need temperature control, another needs a 4 to 20 mA display, a conveyor requires counting, a pump panel needs phase protection, and the main distribution board needs voltage, current and energy monitoring. All of them may also depend on the correct DC power supply.

This is why OEMs should not select panel instruments one model at a time.

They should build a panel instrument architecture.

Radical TechMart's Multispan category currently covers temperature controllers, process control instruments, programmable timers and counters, power and energy meters, protection relays and power supplies.

For an OEM or panel builder, the useful question is therefore not, "Which Multispan product should I buy?"

It is:

What function does this panel need, what signal is available, what action must happen, and which instrument family performs that job?

What Are Industrial Panel Instruments?

Industrial panel instruments are devices installed inside or on the front of an electrical or automation panel to measure, display, control, count, time, protect or power part of the process.

A typical panel may contain instruments responsible for:

The mistake is treating these as independent purchasing items.

For an OEM, they become part of one repeatable machine design.

For a panel builder, they become part of one electrical architecture that must be easy to wire, commission and service.

1. Temperature Controllers: Start With the Sensor and Control Method

Temperature controllers are common in heater panels, packaging machines, sealing equipment, ovens, dryers, extrusion systems and other thermal processes.

Multispan's TC series, for example, is currently offered in different panel sizes and supports common industrial temperature inputs such as J type thermocouple, K type thermocouple and Pt100 RTD, with relay and SSR related control options depending on configuration.

For a panel builder, the first question should not be the display size.

Start with:

Sensor → Required control action → Output device → Panel size

If a heater bank is switched through an SSR, the controller output requirement is different from a small load operated directly through a relay.

Similarly, choosing a Pt100 based controller for an installation designed around a K type thermocouple creates a wiring and commissioning problem before the machine even starts.

What OEMs should confirm

Confirm the sensor type, temperature range, ON/OFF or proportional control requirement, relay or SSR output, auxiliary supply, alarm requirement and panel cutout.

Do not standardize a temperature controller only because it physically fits your standard enclosure.

Standardize it because its input and output architecture fits the machines you build repeatedly.

2. Process Indicators: When a 4 to 20 mA Signal Needs a Human Readout

Many field instruments do not provide a convenient panel display.

A pressure transmitter may provide 4 to 20 mA. A level transmitter may provide the same. A flow or other process transmitter may provide 0 to 10 V or another analog signal.

The PLC can read that signal, but sometimes the operator still needs a local numerical display.

That is the role of a process indicator.

Radical TechMart currently lists Multispan PI series process indicators for signals including 4 to 20 mA, 0 to 20 mA and 0 to 10 VDC, with multiple panel sizes available.

Consider a tank level panel.

The transmitter sends 4 to 20 mA, but an operator does not want to interpret "12.8 mA." The panel indicator can scale the electrical signal into an engineering value such as percentage, litres or metres, depending on configuration.

The important point is that the display must match the signal.

A process indicator is not selected by parameter name alone.

It is selected by:

Input signal + scaling requirement + display size + output requirement

3. Timers: Decide What Must Happen After Time Expires

Timers often look like simple panel accessories until the sequence becomes complicated.

They are used in applications such as:

Radical TechMart currently lists Multispan programmable timer families including UTR series devices along with other time control products.

An OEM should define the timing logic before choosing the timer.

Ask:

What starts the timer?

What should happen when the timing period ends?

Does the machine require ON delay, OFF delay, cyclic operation or another timing function?

How many relay outputs are required?

A timer with the wrong timing mode creates the kind of commissioning problem that often gets blamed on wiring.

The wiring may be correct. The product selection may be wrong.

4. Counters: Counting Production Is Different From Measuring Length

Not every counter solves the same problem.

A machine may need to count pieces, batches, strokes, revolutions or material length.

Multispan's BC series is currently positioned as a batch counter with totalising functionality, dual display and support for industrial sensor inputs.

The LC series, in comparison, is designed around length and speed related measurement using proximity or encoder inputs, with applications such as textile, printing and extrusion machinery.

This difference matters to machine builders.

A packaging machine counting bottles needs different logic from an extrusion line measuring metres of material.

Selection logic for counters

Start with the physical event being measured.

Then identify the sensor producing the pulse.

After that, determine whether the panel needs only indication or also needs a relay action when a preset quantity is reached.

For a batch process, the counter may become part of the machine sequence rather than just a display.

5. Power and Energy Meters: Decide Whether You Need Indication or Energy Data

Electrical panels often need voltage and current monitoring.

But not every panel needs full energy analysis.

This distinction can reduce both unnecessary cost and unnecessary configuration.

The Multispan AVF family includes products focused on electrical parameters such as voltage, current and frequency. For example, the AVF 19N supports panel monitoring across single phase and three phase systems with programmable CT configuration.

The AVH 14 moves further into multifunction energy monitoring with parameters including energy, voltage, current and power factor, plus programmable CT/PT functionality.

For an OEM, think in two levels:

Do not install a complete energy meter simply because it has more functions.

Equally, do not install a basic VAF meter when the customer's project specification requires kWh or power factor data.

6. Protection Relays: Protect the Equipment Before the PLC Has to React

A PLC can monitor a lot of things, but dedicated electrical protection should not automatically be replaced by software logic.

Multispan's protection relay category currently includes MPD, CPR, SPP and ELR families covering motor or phase related protection, current protection, single phasing or phase sequence applications and earth leakage monitoring.

For OEM and panel work, this category becomes especially relevant in:

The right relay depends on the fault you are trying to detect.

A phase sequence problem is not the same as overcurrent.

Earth leakage is not the same as overload.

Motor protection may require monitoring more than one electrical condition.

The selection process should therefore begin with:

What failure must this panel detect before equipment damage or unsafe operation occurs?

Then select the relay category.

7. SMPS: Every DC Device Depends on This One Selection

A sophisticated PLC panel can behave very badly if the DC supply is incorrectly sized.

Radical TechMart currently lists Multispan SMPS families covering 5 V, 12 V, 15 V and 24 V DC requirements, including PS5, PS12, PS15, PS24 and PSW families.

The SMPS should be selected only after calculating the control load.

Consider everything connected to the DC bus:

PLC, I/O modules, HMI, transmitters, proximity sensors, relay coils, communication devices and solenoid loads.

Then calculate the expected current and choose a supply with appropriate capacity for the actual design.

Do not use the same 24 V SMPS for every panel just because it is already present in your BOM library.

Machine A may require 2 A.

Machine B may require 6 A.

Standardization is valuable, but blind standardization is not.

How an OEM Should Standardize Multispan Panel Instruments

The most efficient OEMs do not create a completely new component list for every machine.

They create an approved component matrix.

For example:

This approach reduces engineering time.

It also improves purchasing consistency, drawing standardization, commissioning and spare management.

But every "standard" product needs clearly defined limits.

The moment a new machine falls outside those limits, recheck the selection.

Panel Size and Cutout Should Be Decided Early

Many panel instruments are available in different front dimensions.

This affects:

This becomes especially important when an OEM redesigns an existing machine.

Changing from one panel meter size to another after the enclosure is fabricated creates unnecessary mechanical rework.

Instrumentation selection should therefore happen before the final GA and panel door layout are released.

Inputs and Outputs Matter More Than the Front Display

Two controllers can look almost identical from the front and perform completely different jobs.

Before adding any panel instrument to a BOM, identify:

Input: What enters the instrument?

Examples include thermocouple, Pt100, 4 to 20 mA, voltage, CT signal, pulse input or dry contact.

Output: What leaves the instrument?

Examples include relay, SSR drive, alarm contact, pulse output or another signal.

Action: What happens next?

Display only, alarm, machine stop, heater control, counting completion, motor protection or communication to another system.

This three step check prevents a large percentage of panel selection mistakes.

Common Mistakes OEMs and Panel Builders Should Avoid

Do This, Not That

Quick Selection Checklist for Panel Builders

Before finalizing a Multispan panel instrument, confirm:

1. What job must the instrument perform?
2. What signal or sensor is connected to its input?
3. What measurement range is required?
4. Is the instrument for indication, control, alarm or protection?
5. What output is required?
6. What supply voltage is available?
7. What panel cutout is available?
8. Does it need relay, SSR, pulse or other output?
9. Does the panel need communication with PLC, HMI or SCADA?
10. What environmental conditions will the instrument face?
11. Is the selected model part of the OEM standard BOM?
12. Can maintenance replace it easily?
13. Are the terminal arrangement and wiring practical?
14. Has the latest product datasheet been checked before release?

Specifications to Confirm Before Purchase

Specifications vary between Multispan product families and individual models.

Before final selection, confirm the input type, measurement range, output type, relay rating, auxiliary supply, accuracy, panel dimensions, panel cutout, mounting style, display configuration, protection functions, communication options, environmental conditions, terminal arrangement and compatibility with the rest of the control system.

For meters, also confirm CT and PT requirements.

For counters, confirm pulse source and sensor compatibility.

For controllers, confirm sensor and control output.

For SMPS products, confirm DC voltage, rated current and connected load.

Why Multispan Categories Are Useful for OEM and Panel Standardization

The Multispan category structure on Radical TechMart brings several common control panel functions into one product ecosystem: temperature control, process instrumentation, timers and counters, electrical measurement, protection and power supplies.

For an OEM, that makes it easier to develop a controlled set of approved panel components rather than sourcing every function independently.

For a panel builder, the advantage is clarity.

A requirement can be separated into categories first, then into specifications, then into the exact model.

That is a much safer process than starting with a product code and trying to make it fit the application.

Final Thoughts

Industrial panel design becomes easier when instruments are selected by function instead of by habit.

A temperature controller should begin with the sensor and control load.

A process indicator should begin with the signal.

A timer should begin with the sequence.

A counter should begin with the event being measured.

An electrical meter should begin with the parameters the customer actually needs.

A protection relay should begin with the fault condition.

An SMPS should begin with the DC load.

For OEMs and panel builders, this way of thinking creates better drawings, cleaner BOMs, faster commissioning and easier maintenance.

The right Multispan industrial panel instrument is not simply the model already used in the previous machine.

It is the model whose input, output, function, size and electrical requirements match the panel being designed today.

FAQs

1. What Multispan products are commonly used in industrial control panels?

Multispan's current Radical TechMart categories include temperature controllers, process related instruments, timers, counters, power and energy meters, protection relays and industrial power supplies.

2. How should an OEM choose a panel instrument?

Start with the required function, then confirm input signal, output requirement, supply voltage, panel size, control action and integration requirements. Select the model only after those points are defined.

3. What is the difference between a process indicator and a temperature controller?

A process indicator primarily displays a compatible process signal. A temperature controller receives a temperature sensor input and can operate an output to regulate the process.

4. When should a panel builder use a VAF meter instead of an energy meter?

Use VAF monitoring when the main requirement is voltage, current and frequency indication. If the customer also needs power factor, energy consumption or related energy parameters, evaluate a multifunction energy meter instead.

5. Why are panel cutout dimensions important?

The selected instrument must physically fit the panel door or enclosure. Changing dimensions after fabrication can require mechanical rework and may affect the complete panel layout.

6. Which Multispan products can be used for production counting?

Radical TechMart currently lists Multispan batch counters, general counters and length counting products. The correct type depends on whether the machine needs piece counting, batching, length measurement or another pulse based measurement.

7. Why does an industrial panel need a protection relay if it already has a PLC?

A dedicated relay can monitor specific electrical fault conditions independently of normal control logic. The required relay should be selected according to the actual protection function, such as phase, current, motor or earth leakage protection.

8. How should an SMPS be selected for an OEM panel?

Confirm the required DC voltage, calculate the combined current consumption of all connected loads, consider operating conditions and available panel space, then compare the appropriate power supply model. Radical TechMart currently lists Multispan supplies across several DC voltage and current ranges.

A protection relay is often purchased only after something has already gone wrong.

A motor has burnt after single phasing. A pump has run dry. A conveyor has overloaded. A machine is drawing abnormal current. An insulation fault is causing earth leakage. Or a newly wired three phase motor is rotating in the wrong direction because the phase sequence has changed.

At that point, the question is usually not, "Which relay has the most features?"

The real question is, "Which electrical fault are we trying to stop before it damages the equipment?"

That is the right way to select a protection relay.

Radical TechMart's current Multispan Protection Relays category includes products for broad motor protection, current protection, phase protection and earth leakage monitoring, including MPD 13N, MPD 19N, CPR 126, CPR 22U, SPP 22 and the ELR series.

These products should not be selected only by price or enclosure size. The correct relay depends on the load, electrical fault, current sensing method, trip logic, reset philosophy, mounting arrangement and the equipment that must be disconnected when a fault occurs.

What Is an Industrial Protection Relay?

An industrial protection relay continuously monitors an electrical condition and changes its output when that condition moves outside an acceptable limit.

In simple words, it watches the electrical system and tells the control circuit when something is wrong.

The relay itself usually does not interrupt a large motor current directly. Its output is typically connected into a control circuit that can operate a contactor, breaker trip circuit, alarm, PLC input or another protection device.

Depending on the relay, it may monitor conditions such as:

• Phase failure
• Wrong phase sequence
• Current overload
• Current underload
• Short circuit condition
• Current imbalance
• Locked rotor
• Earth leakage
• Voltage abnormalities
• Three phase asymmetry

The first selection question should therefore always be:

What fault must the relay detect?

Why Protection Relays Matter in Actual Plant Conditions

Consider a three phase pump.

During normal operation, all phases are healthy and the motor draws current within its expected range.

Now imagine one phase is lost.

The motor may continue trying to operate under an abnormal condition. Current can become unbalanced, heating can increase and the motor may eventually fail if the condition continues.

Now consider a borewell or process pump.

The electrical supply may be perfectly healthy, but if the pump loses water, the mechanical load can reduce. That can appear as an undercurrent condition.

A relay selected only for phase failure may not solve that problem.

This is why protection has to match the actual failure mode.

A purchase team may compare relay prices, but the maintenance team deals with the consequences when the wrong protection philosophy is used.

Main Types of Multispan Industrial Protection Relays

1. Phase Protection Relays

Phase protection is one of the most common requirements in three phase motor and pump panels.

The Multispan SPP 22 portion of the SPP 22 / V22 RYB combination is designed around phase loss, phase asymmetry and incorrect phase sequence protection. The V22 RYB portion provides visual R, Y and B phase indication.

Best for:

Three phase pumps, motors, compressors, HVAC equipment and machines where phase condition must be checked before operation.

Why this type makes sense:

If the main risk is missing phase, reversed phase sequence or excessive phase imbalance, there may be no need to begin with a more complex current protection device.

For example, wrong phase sequence can cause a three phase motor to rotate in the opposite direction. On pumps, compressors or mechanical systems, that can become an operational problem immediately.

Selection caution:

A phase protection relay does not automatically provide full overload, underload or earth leakage protection. Confirm every required fault separately.

2. Overcurrent and Undercurrent Protection Relays

Current tells you a great deal about what is happening to a motor or electrical load.

Too much current can indicate overload, mechanical jamming or another abnormal operating condition.

Too little current can also matter.

For pumps, fans and certain machinery, undercurrent may indicate loss of load, dry running, broken coupling or another process problem.

The Multispan CPR 22U is a compact programmable overcurrent and undercurrent relay suitable for single phase and three phase systems. It also provides selectable fail safe and non fail safe operation.

Best for:

Applications where the primary protection decision should be based on current.

Why this model type makes sense:

Instead of only checking whether all phases are present, a current relay can identify whether the machine is actually operating within the expected load window.

This becomes particularly useful in pump panels, DG panels, MCCs and industrial machinery.

Selection caution:

Before selecting a current relay, identify the expected running current, starting current and fault current. An incorrectly chosen trip threshold can produce nuisance trips or inadequate protection.

3. Three Phase Current Protection Relays

For larger three phase loads, the protection logic may need to go beyond a simple overcurrent setting.

The Multispan CPR 126 is a three phase True RMS current protection relay designed around overload, underload, current asymmetry and single phase prevention. Its product information also references programmable CT ratios, which makes it relevant where load current is measured through external current transformers.

Best for:

Three phase motors, pumps, industrial loads and machinery where current condition across all phases matters.

Why this model makes sense:

Imagine a motor where one phase is drawing noticeably more current than the others.

The total load may still appear reasonable, but the imbalance itself can indicate an abnormal electrical or mechanical condition.

A three phase current relay gives the protection system more information than a simple single current threshold.

Selection caution:

Confirm CT ratio, expected full load current and actual protection settings before commissioning.

4. Multifunction Motor Protection Devices

Sometimes one fault is not enough.

A critical motor may need protection from:

• Overcurrent
• Undercurrent
• Current unbalance
• Locked rotor
• Short circuit
• Phase loss
• Reverse phase

This is where a broader motor protection device becomes useful.

The Multispan MPD 13N combines several protection functions in a 96 × 96 mm panel mounted format. Radical TechMart's current product information lists overcurrent, undercurrent, unbalance, short circuit, locked rotor, phase loss and reverse phase protection. It also lists optional RS485 Modbus communication on request.

Best for:

Important motors, pumps, compressors, production equipment and industrial machinery where multiple electrical failure modes should be monitored from one device.

Why this model makes sense:

Instead of installing separate devices for several related motor faults, a multifunction protection device can centralize the protection logic and provide clearer monitoring.

This is useful when downtime is expensive and operators need more information about why a machine tripped.

Selection caution:

More functions only help when they are commissioned properly.

Do not install a multifunction protection relay and leave every threshold at an assumed value. Motor current, trip delays and fault thresholds should reflect the actual machine.

5. Compact Multifunction Protection

The Multispan MPD 19N is another three phase protection device in the current category. Radical TechMart describes it as providing real time voltage and current monitoring together with programmable protection parameters and tripping control.

This type is useful when the panel needs visible electrical monitoring together with protection.

Best for:

Industrial machinery, pumps and electrical panels where operators benefit from both protection and a clear local display.

Selection caution:

Confirm the exact protection functions and input requirements from the latest datasheet before treating two MPD models as interchangeable.

6. Earth Leakage Relays

Earth leakage protection solves a different problem.

Instead of looking mainly at normal load current, an earth leakage relay monitors current escaping from the intended circuit path toward earth.

Leakage can appear because of deteriorated insulation, damaged cables, moisture, equipment faults or other electrical problems.

The Multispan ELR 19N and ELR 35 are currently listed in the Protection Relays category. Both are described with adjustable leakage sensitivity from 30 mA to 30 A. The ELR 19N uses a panel mount format, while the ELR 35 is designed for DIN rail installation.

Both product pages also indicate the use of a separate core balance current transformer, or CBCT, for leakage sensing.

Best for:

LT panels, MCCs, pump panels, DG panels, distribution boards and industrial machinery where earth leakage monitoring is required.

Why this type makes sense:

An overload relay and an earth leakage relay are not performing the same job.

A circuit can have acceptable load current while still developing dangerous leakage to earth.

Selection caution:

Do not buy only the ELR and forget the CBCT requirement. Confirm CBCT size, conductor arrangement and required leakage sensitivity before ordering.

How to Choose the Right Protection Relay

A practical selection process begins with the failure you are trying to prevent.

The important part is not memorizing this table.

It is understanding why the fault happens.

Check the Current Sensing Method

Before selecting any current based protection relay, determine how the current reaches the device.

For smaller current ranges, a relay may accept current directly within its specified input.

For higher current applications, external CTs may be required.

When a CT is involved, confirm:

1. CT primary current
2. CT secondary current
3. Relay input requirement
4. Programmable CT ratio
5. Full load motor current
6. Starting current
7. Required trip threshold

A wrong CT ratio can make the displayed current and the protection setting incorrect.

Decide Between Panel Mount and DIN Rail

Mounting becomes especially important in replacement projects.

A panel mounted relay provides front access and visible indication from outside the enclosure.

A DIN rail relay is normally installed inside the panel alongside contactors, terminals, MCBs and other control components.

For example, ELR 19N is positioned as a panel mount earth leakage relay, while ELR 35 is a DIN rail version.

Choose according to panel architecture, operator visibility, available space and maintenance access.

Understand Fail Safe Operation

Fail safe logic matters in protection systems.

In fail safe operation, the relay state is arranged so that certain failures, including loss of power to the protection device, can move the control circuit toward a safe condition.

The CPR 22U specifically provides selectable fail safe and non fail safe operation.

Before commissioning, determine what the machine should do when:

• A protection fault occurs
• Supply to the relay fails
• The sensor or CT circuit is abnormal
• The fault disappears
• An operator presses reset

These questions are more important than simply asking whether the relay has NO and NC contacts.

Auto Reset or Manual Reset?

Automatic reset can be convenient where the process is expected to restart after the electrical condition returns to normal.

But automatic restart is not appropriate for every machine.

On equipment where unexpected restarting could create a mechanical or personnel hazard, the control philosophy may require manual intervention.

Always consider the complete machine safety circuit before deciding the reset method.

Common Mistakes to Avoid

Selecting one relay for every fault: Phase failure, overload and earth leakage are different problems.

Setting protection values without motor data: Full load current and actual operating conditions should guide the settings.

Ignoring starting current: Motors can draw significantly different current during starting compared with normal running.

Using undercurrent without understanding the process: Undercurrent can be useful for dry running or loss of load, but the correct threshold depends on the machine.

Ignoring CT ratio: Current protection is only as accurate as its measurement configuration.

Confusing earth leakage with overload protection: They detect different fault conditions.

Forgetting the CBCT: Earth leakage relay installations often depend on the correct CBCT arrangement.

Selecting by enclosure size alone: Two relays that fit the same panel space may perform completely different functions.

Do This, Not That

Quick Selection Checklist

Before selecting a Multispan protection relay, confirm:

1. What equipment is being protected?
2. Is the supply single phase or three phase?
3. What fault must be detected?
4. Is phase failure protection required?
5. Is phase sequence protection required?
6. Is overload protection required?
7. Is underload protection required?
8. Is current imbalance protection required?
9. Is earth leakage protection required?
10. What is the full load current?
11. What CT ratio is being used?
12. Is a CBCT required?
13. What trip delay is acceptable?
14. Should the relay reset automatically or manually?
15. Is fail safe operation required?
16. What relay output must operate?
17. Is panel mount or DIN rail preferred?
18. Is PLC or SCADA communication required?
19. Has the final setting philosophy been approved by the electrical engineer?
20. Has the latest datasheet been checked before ordering?

Specifications to Confirm Before Purchase

Specifications vary between relay models. Final details should always be confirmed from the latest manufacturer datasheet before purchase.

Check:

• Supply voltage
• Number of phases
• Monitoring range
• Current input
• CT ratio
• Leakage sensitivity
• CBCT requirement
• Overcurrent setting
• Undercurrent setting
• Phase failure protection
• Phase sequence protection
• Current asymmetry setting
• Trip delay
• Recovery delay
• Reset type
• Fail safe logic
• Relay output and contact rating
• Panel mount or DIN rail mounting
• Panel cutout where applicable
• Display and indication
• Communication requirement
• PLC or SCADA integration
• Installation environment

Why Buy Multispan Protection Relays from Radical TechMart?

The important part of protection relay selection is not finding a relay that can trip.

It is finding a relay that trips for the right reason.

Radical TechMart's current Multispan Protection Relays category includes products for phase protection, current protection, multifunction motor protection and earth leakage monitoring.

For a useful technical inquiry, provide your equipment type, motor current, supply system, CT details, fault protection requirement, mounting preference and required control output.

That information makes it much easier to compare the correct relay family instead of selecting only from a model number.

Final Thoughts

A Multispan industrial protection relay should be selected around the failure mode of the equipment.

If the problem is phase loss or wrong phase sequence, begin with phase protection.

If the machine must be protected from abnormal current, consider overcurrent and undercurrent protection.

If several motor faults must be monitored together, a multifunction protection device may be more appropriate.

If the concern is current leaking to earth, use an earth leakage protection strategy with the correct ELR and CBCT arrangement.

In an industrial panel, good protection is not about adding the maximum number of relays.

It is about understanding what can fail, detecting that condition early and making the machine respond safely before a small electrical problem becomes expensive downtime.

FAQs

1. What is a Multispan protection relay?

A Multispan protection relay monitors electrical conditions such as phase status, current or earth leakage and changes its relay output when a programmed fault condition occurs.

2. Which relay should I use for phase failure protection?

For applications primarily concerned with phase loss, phase imbalance and incorrect phase sequence, a phase protection device such as Multispan SPP 22 can be considered.

3. What is the difference between CPR 22U and CPR 126?

CPR 22U is a compact programmable overcurrent and undercurrent relay suitable for single phase and three phase applications. CPR 126 is oriented toward three phase current protection with functions including overload, underload and asymmetry monitoring.

4. What is the use of MPD 13N?

MPD 13N is intended for broader three phase equipment protection and includes functions such as overcurrent, undercurrent, current unbalance, locked rotor, phase loss and reverse phase protection.

5. What is an earth leakage relay used for?

An earth leakage relay detects leakage current flowing toward earth and operates its output when leakage crosses the selected threshold.

6. What is the difference between ELR 19N and ELR 35?

Both are used for earth leakage monitoring. The ELR 19N is a panel mount model, while the ELR 35 is designed for DIN rail mounting.

7. Does an earth leakage relay require a CBCT?

The current Radical TechMart product information for ELR 19N and ELR 35 indicates that a separate core balance CT is required for leakage sensing.

8. Can Multispan protection relays connect to PLC or SCADA?

Communication depends on the model. For example, MPD 13N is listed with optional RS485 Modbus communication on request. Always confirm the communication variant before ordering.

A panel builder may receive a requirement that simply says, "Multifunction meter required."

That sounds clear until the panel design actually starts.

Does the customer only want to see voltage and current? Is frequency required? Does the maintenance team need power factor? Does management want kWh consumption? Will the meter work through external CTs? Is the panel 72 × 72 mm or 96 × 96 mm? Will the measurement eventually need to reach an energy management system?

These questions change the meter selection completely.

This is where many buyers make a mistake. They compare two digital meters because both look similar from the front, while their actual measurement functions can be very different.

Radical TechMart's current Multispan Power & Energy Meter category reflects this difference. It includes VAF focused models such as AVF 19N, AVF 133 and AVF 29T, as well as energy focused models such as AVH 13N and AVH 14.

The right way to choose a Multispan multifunction meter is therefore to begin with the electrical requirement, not the model number.

What Does a Multifunction Meter Actually Do?

A multifunction meter combines several electrical measurements into one panel mounted instrument.

Instead of installing separate voltmeters, ammeters, frequency meters and energy meters, one instrument can monitor multiple electrical parameters, depending on the model.

Typical parameters may include:

The important phrase here is depending on the model.

A meter that displays voltage, current and frequency should not automatically be treated as an energy meter. If the project requires kWh, power factor or kW monitoring, confirm those functions before ordering.

First Decide: Do You Need VAF Monitoring or Energy Monitoring?

This is the most useful starting point.

If the panel only needs basic electrical health monitoring, voltage, current and frequency may be enough.

For example, an operator checking a pump panel may mainly want to confirm whether all three phases are available, whether current is within the expected range and whether supply frequency is normal.

In that case, a VAF type meter can make more sense than paying for energy functions that nobody will use.

The Multispan AVF 19N is positioned for voltage, current and frequency monitoring and supports single phase and three phase wiring configurations with programmable CT ratios.

But consider another panel where management wants to track energy consumption of a production line.

Now voltage and current are not enough.

The meter may also need to show kW, power factor and accumulated kWh. Models such as Multispan AVH 13N and AVH 14 are designed around broader power and energy measurement.

The selection question is therefore simple:

Do you only need to know what the electrical system is doing right now, or do you also need to know how much power and energy it is using?

Understand Your Electrical Wiring System

Before selecting the meter, identify how the electrical system is wired.

Common configurations include:

Never assume that every three phase multifunction meter supports every wiring arrangement.

For example, the AVH 14 product information lists support for 1 phase 2 wire, 3 phase 3 wire and 3 phase 4 wire systems. The AVH 13N listing is specifically described around a three phase 4 wire input system.

That difference matters during panel design.

A technically capable meter is still the wrong meter if its connection system does not match the incoming supply.

CT Selection Is More Important Than Many Buyers Expect

In higher current electrical panels, the meter normally does not measure the complete load current directly.

A current transformer, or CT, converts the primary current into a standardized secondary current that the meter can measure.

For example, a feeder carrying hundreds of amperes may use a CT matched to the actual load and meter input.

Before ordering the multifunction meter, confirm:

1. Maximum expected load current
2. CT primary rating
3. CT secondary rating
4. Whether the meter's CT ratio is programmable
5. Whether the CT ratio available in the meter covers the selected transformer

This is particularly important when replacing an existing meter.

Do not simply copy the old meter model. Check the CT already installed inside the panel.

A meter configured for the wrong CT ratio can display a believable number that is still incorrect. That type of error is more dangerous than a completely blank display because operators may trust the reading.

When Does PT Ratio Matter?

For normal low voltage panels, direct voltage measurement may be sufficient when the meter input range matches the electrical system.

For higher voltage systems, potential transformers or voltage transformers may be used.

If PT based measurement is involved, check whether the meter allows the required primary and secondary ratio to be programmed.

The AVH 14 includes programmable CT and PT ratio capability, which is relevant when the meter has to scale transformer based measurements into actual electrical values.

The practical rule is simple:

Never finalize a meter before confirming how both current and voltage will reach it.

Choose Measurements Based on the Job the Panel Must Perform

Do not select the meter with the longest specification sheet.

Select the one that answers the questions the operator, maintenance engineer and energy team actually need answered.

How the Current Multispan Options Fit Different Requirements

The products currently shown in Radical TechMart's Multispan Power & Energy Meter category cover different levels of measurement.

The AVF 133 is listed as a 96 × 96 mm VAF meter with programmable CT ratio and additional phase sequence, RPM and load hour indications. The AVF 29T uses a more compact 72 × 72 mm format and supports programmable CT/PT ratios.

This comparison should be used as a starting point. Final model selection should always be checked against the latest manufacturer datasheet.

Do You Need an Output for Another System?

This question is often forgotten until panel fabrication is nearly complete.

Ask whether the meter is only for local display or whether its information also needs to reach another system.

Possible requirements may include:

Do not assume that every multifunction meter provides communication simply because it measures many parameters.

For example, Radical TechMart's AVH 14 listing identifies a programmable energy pulse output.

If PLC, SCADA or Modbus communication is required, confirm the exact communication interface on the selected model before purchase.

This requirement should be finalized during panel design, not after the meter has already been installed.

Panel Size and Cutout Can Decide the Model

Electrical performance is only part of the selection.

The meter must physically fit the panel.

Common panel meter formats include 72 × 72 mm and 96 × 96 mm, among others.

Radical TechMart lists the AVF 29T in a 72 × 72 mm format, while models such as AVF 19N, AVF 133, AVH 13N and AVH 14 are associated with the 96 × 96 mm class.

This becomes especially important during replacement jobs.

Before ordering, measure the existing panel cutout rather than only measuring the visible front bezel.

Accuracy Should Match the Purpose

A panel meter used for general operational monitoring does not always need the same accuracy requirement as a meter used for detailed energy analysis.

Higher specification does not automatically mean better selection.

Ask what decision will be made from the measurement.

If the value is used only for general operator monitoring, one level of accuracy may be sufficient. If energy performance, load analysis or engineering calculations depend on the reading, measurement accuracy becomes more important.

For commercial billing or revenue metering, do not assume a normal panel multifunction meter is automatically suitable. Confirm the applicable metering standards, approvals and accuracy requirements separately.

Common Mistakes to Avoid

Selecting by price only: A cheaper meter is expensive if it does not measure the parameter the project needs.

Calling every VAF meter an energy meter: Voltage, current and frequency monitoring is not the same as kWh measurement.

Ignoring the CT ratio: Incorrect CT configuration produces incorrect displayed current and power values.

Not checking the wiring system: A meter must match the actual single phase or three phase connection.

Ignoring panel cutout size: Electrical compatibility does not solve a mechanical fitment problem.

Assuming communication is standard: Confirm pulse output, RS485 or Modbus requirements model by model.

Buying too many functions: Additional features create no value if the plant will never use them.

Buying too few functions: A basic meter can become an expensive replacement job when the customer later asks for energy or communication data.

Do This, Not That

Quick Selection Checklist

Before choosing a Multispan multifunction meter, confirm:

1. Is the system single phase or three phase?
2. Is it 3 wire or 4 wire?
3. Do you need only voltage, current and frequency?
4. Do you also need kW, kVA, kVAr, PF or kWh?
5. What is the maximum current?
6. What CT ratio will be used?
7. Is PT based measurement required?
8. What accuracy is required?
9. What panel size and cutout are available?
10. Is pulse output required?
11. Is RS485 or Modbus communication required?
12. Does the data need to reach PLC, HMI, SCADA, BMS or EMS?
13. What auxiliary supply is available?
14. Has the final configuration been checked against the latest datasheet?

Specifications to Confirm Before Purchase

Specifications may vary depending on the Multispan model and configuration. Confirm the official datasheet before final selection.

Check the measuring parameters, wiring system, input voltage range, current input, CT primary and secondary ratio, PT ratio, accuracy class, panel dimensions, panel cutout, display type, auxiliary supply, output options, communication protocol, pulse output requirement, front protection rating and installation environment.

For replacement applications, also confirm the existing meter's wiring, CT ratio and cutout before removing it.

Why Buy Multispan Power & Energy Meters from Radical TechMart?

A customer asking for a "multifunction meter" may actually need anything from a simple VAF display to a complete energy monitoring instrument.

At Radical TechMart, the selection can begin with the actual panel requirement: electrical system, measurement parameters, CT/PT configuration, cutout size, output requirements and final monitoring architecture.

The current Multispan Power & Energy Meter category includes VAF meters, multifunction energy meters, voltmeters, ammeters and combined panel meters for different electrical monitoring requirements.

The objective is not to select the meter with the maximum number of features. It is to select the meter whose functions match the electrical panel.

Final Thoughts

Choosing a Multispan multifunction meter for an electrical panel becomes much easier once the requirement is separated into a few practical questions.

First decide what needs to be measured. Then confirm the electrical wiring system, CT/PT arrangement, panel size, accuracy and integration requirement.

If the job only needs voltage, current and frequency, a VAF meter may be the practical choice.

If the plant needs power factor, kW and accumulated energy, move toward a multifunction energy meter.

And if the measurement needs to become part of a larger automation or energy management system, define the required output or communication interface before ordering.

In an electrical panel, the right meter is not selected because it displays the most numbers. It is selected because it provides the right electrical information to the right person or control system.

FAQs

1. What is a Multispan multifunction meter?

A Multispan multifunction meter is a panel mounted electrical measuring instrument that can monitor multiple parameters such as voltage, current, frequency, power, power factor or energy depending on the selected model.

2. What is the difference between a VAF meter and an energy meter?

A VAF meter primarily monitors voltage, current and frequency. An energy meter can additionally measure parameters such as power, power factor and accumulated energy such as kWh, depending on its configuration.

3. Which Multispan meter is suitable for energy monitoring?

Models such as AVH 13N and AVH 14 are positioned for multifunction power and energy monitoring. Final selection should be based on the required electrical parameters, wiring system and CT/PT requirements.

4. Can a multifunction meter work with an external CT?

Many industrial multifunction meters support external CTs. The programmed CT ratio must match the actual CT installed in the electrical panel.

5. Why is CT ratio important in a multifunction meter?

The meter uses the CT ratio to convert the measured secondary current into the actual primary current. An incorrect CT ratio results in incorrect displayed current, power and energy values.

6. Can a multifunction meter connect to PLC or SCADA?

It depends on the model. If PLC or SCADA integration is required, confirm whether the selected meter provides RS485, Modbus, pulse output or another compatible interface before purchase.

7. Should I choose a 72 × 72 mm or 96 × 96 mm multifunction meter?

Choose according to available panel space, cutout dimensions, display requirement and model functionality. For replacement projects, measure the existing cutout before ordering.

8. What should I provide when asking for a multifunction meter quotation?

Provide the electrical system type, required parameters, maximum current, CT ratio, PT requirement, panel cutout, auxiliary supply and any pulse or communication requirement.

A packaging machine may need to wait three seconds before starting the next operation. A motor panel may need a timed star to delta changeover. A conveyor may need to count every product passing a sensor. A textile machine may need to measure how many metres of material have been processed.

All four applications involve automation, but they do not need the same instrument.

The first two are mainly time based operations. The last two are mainly count based operations.

This is the basic difference between industrial timers and counters.

Multispan's timer range on Radical TechMart includes universal programmable timers, ON/OFF delay timers, cyclic timers, forward reverse timers, star delta timers, power OFF delay timers, time totalisers and thumbwheel timers. The category also covers broader timer functions such as programmable, sequential, thumbwheel and real time clock based timing.

On the counting side, Radical TechMart lists Multispan batch counters and length counters for applications such as production counting, batch control and length measurement.

The right starting point is therefore not the model number.

Start by asking one question:

Does the machine need to act according to time, or according to a number of events?

What Is an Industrial Timer?

An industrial timer controls an operation according to a selected time interval.

A simple example is a motor that should start five seconds after a control signal is received.

The timer receives the trigger, measures the programmed time and changes its output when the timing condition is reached.

A typical sequence looks like:

Input Signal → Timer → Time Delay → Relay Output → Machine Action

Timers are commonly used where a machine needs a delay, repeated ON and OFF sequence, motor changeover, operating period or timed switching function.

Multispan's current range includes UTR universal timers as well as dedicated products for cyclic timing, forward reverse operation, ON/OFF delay, star delta timing and power OFF delay.

What Is an Industrial Counter?

A counter works with events rather than elapsed time.

Each time a sensor, encoder, micro switch or another compatible input generates a pulse, the counter records it.

For example:

Product Passes Sensor → Sensor Generates Pulse → Counter Adds 1

If 100 bottles pass the sensor, the counter can display 100.

Depending on the type of counter, it may also operate a relay when the programmed quantity is reached.

This makes counters useful for production quantity, batch counting, machine cycles, material length and other repetitive industrial processes.

Timer vs Counter: The Simple Difference

The confusion usually happens because both products may have a digital display, setting buttons and relay outputs.

Their purpose, however, is different.

Types of Multispan Industrial Timers

Universal Programmable Timers

A universal timer is useful when one panel or machine may require different timing functions.

Rather than designing a separate timer for every basic delay requirement, a programmable timer provides greater flexibility.

Radical TechMart currently lists Multispan UTR series products including UTR 413, UTR 433, UTR 1033, UTR 2033 and larger UTR 1244, UTR 2244 and UTR 4244 variants.

Best suited for: machine builders, OEM panels and automation applications where timing requirements may vary.

The main selection point is not simply the maximum time range. Confirm the timing mode, trigger method, number of outputs and required supply before selecting the model.

ON/OFF Delay Timer

An ON delay or OFF delay timer is useful when an output should change state after a defined delay.

For example:

A cooling fan may need to continue running after the main machine is switched OFF.

A conveyor may need to wait before another process starts.

Radical TechMart lists the Multispan DI 22 as an ON/OFF delay timer and the POD 30S as a power OFF delay timer.

Best suited for: machine sequencing, delayed switching and auxiliary control circuits.

Cyclic Timer

A cyclic timer repeatedly switches between ON and OFF periods.

Consider a lubrication pump that should run for a short period every few minutes.

Instead of continuously running the pump, the timer creates a repeating cycle:

ON → OFF → ON → OFF

Radical TechMart lists the Multispan CYL 22U specifically as a cyclic timer for industrial DIN rail applications.

Best suited for: repeated machine operations, lubrication cycles, intermittent equipment and repetitive control sequences.

Forward Reverse Timer

Some motor applications require alternating forward and reverse operation.

A timer can manage the changeover sequence so the motor operates in one direction for a selected period and then changes according to the required control logic.

The Multispan FRT 22U is listed as a forward reverse timer with dual relay outputs and a pause function.

Best suited for: equipment requiring repetitive directional operation.

The motor control circuit, interlocking and contactor arrangement must still be designed correctly. The timer is only one part of the control system.

Star Delta Timer

A star delta timer is designed for motor starting circuits where the motor initially runs through the star connection before changing to delta.

Radical TechMart lists the Multispan SDX 22 as a star delta timer with separate timed switching functionality for this purpose.

Best suited for: conventional star delta motor starter panels.

When selecting this timer, confirm the motor starter design and required transition timing instead of selecting only by supply voltage.

Time Totaliser

A time totaliser answers a different question:

How long has this equipment actually been operating?

The Multispan DTT Series is listed as a time totaliser or hour meter with a six digit display.

This can be useful for:

• Machine running hour monitoring
• Preventive maintenance planning
• Pump running time
• Generator or equipment operating hours
• Service interval tracking

A time totaliser does not necessarily control the machine. Its main job is to record accumulated operating time.

Types of Multispan Industrial Counters

Batch Counter

Suppose a packaging line needs 50 products in each batch.

A standard total count alone may not be enough. The machine needs to know when each batch reaches 50 while still keeping track of overall production.

This is where a batch counter becomes useful.

The Multispan BC Series listed by Radical TechMart includes separate total and batch displays, supports proximity sensor or micro switch inputs, and provides relay and buzzer outputs for batch operations.

A practical sequence may look like:

Sensor detects product → Counter increases → Preset quantity reached → Relay operates / buzzer alerts

Best suited for:

• Packaging lines
• Filling machines
• Conveyor batches
• Production quantity control
• Printing and labelling equipment
• OEM machine counting

The BC Series is specifically listed for packaging, filling, textile, printing, conveyor and production monitoring applications.

Length Counter

Not every production process is counted in pieces.

Textile, cable, film, paper and extrusion applications often need measurement in metres or another length unit.

A length counter receives pulses from a suitable sensor or encoder and converts them into a meaningful length measurement.

Radical TechMart lists the Multispan LC Series, including LC 1046D, LC 2046, LC 445 and LC 3006, for length and speed measurement using proximity or encoder inputs. The store specifically identifies textile, printing and extrusion as relevant applications.

Best suited for:

• Textile processing
• Cable measurement
• Printing machinery
• Film processing
• Extrusion lines
• Continuous material measurement

The important selection point is the relationship between mechanical movement and the pulse input. Incorrect pulse scaling can produce an incorrect displayed length even when the counter itself is working properly.

The Input Sensor Matters as Much as the Counter

A counter cannot count what it cannot detect.

Before selecting the counter, determine how the event will be sensed.

Depending on the application, this may involve:

• Proximity sensor
• Encoder
• Micro switch
• Machine generated pulse
• Other compatible switching input

The Multispan BC Series supports PNP/NPN proximity sensors or micro switches, while the LC Series is designed around proximity or encoder input for length measurement.

This is where many machine problems begin.

If the sensor misses products, produces multiple pulses for one product or is mounted incorrectly, changing the counter may not solve the problem.

Always inspect the complete sensing arrangement.

How to Choose Between a Timer and Counter

Start with the actual machine requirement.

Choose a timer when:

• The action depends on seconds, minutes or hours
• Equipment must start after a delay
• Equipment must remain ON for a fixed period
• An ON/OFF cycle needs to repeat
• A star delta changeover is required
• Forward and reverse operation requires timing
• Machine operating hours need to be recorded

Choose a counter when:

• Products need to be counted
• A batch must stop at a preset quantity
• Production output needs monitoring
• Machine cycles need to be counted
• Material length needs measurement
• Pulses from a sensor or encoder need to be totalised

In some machines, you may need both.

For example, a packaging machine may count ten products and then wait two seconds before starting the next batch.

The counter decides how many.

The timer decides how long.

Practical Example: Packaging Machine

Consider a machine packing bottles into groups of 12.

A proximity sensor detects every bottle entering the packing section.

The counter records each pulse.

When the count reaches 12, its output can signal the control circuit that the batch is complete.

The machine may then need a short delay before the next cycle starts.

That delay is the timer's job.

So the sequence becomes:

Sensor → Counter → Batch Complete → Timer Delay → Next Machine Cycle

Looking at the process this way makes component selection much easier than trying to start with product model numbers.

Practical Example: Motor Control Panel

Consider a motor that uses a star delta starter.

The motor starts in star configuration.

After the selected period, the timer changes the control sequence so the motor can transition to delta.

For this application, a dedicated star delta timer is more logical than a general production counter.

The Multispan range includes a dedicated SDX 22 star delta timer as well as forward reverse and cyclic timers for other motor control sequences.

Practical Example: Textile or Extrusion Line

Now consider a continuous roll of material.

Counting pieces is not useful because the product is continuous.

Instead, an encoder or suitable proximity arrangement provides pulses related to material movement.

A length counter converts those pulses into length.

Multispan's LC Series is designed for this type of measurement and is listed for textile, printing and extrusion applications.

Common Selection Mistakes

Quick Timer Selection Checklist

Before choosing an industrial timer, confirm:

1. What should happen after the timing period?
2. Is the requirement ON delay, OFF delay, cyclic, forward reverse or star delta?
3. What timing range is required?
4. What starts the timing cycle?
5. How many relay outputs are required?
6. What should happen after power interruption?
7. What supply voltage is available?
8. Is DIN rail or panel mounting required?
9. Is a simple timer sufficient, or is a programmable universal timer required?
10. Has the final model been checked against the datasheet?

Quick Counter Selection Checklist

Before choosing an industrial counter, confirm:

1. What needs to be counted?
2. Is the requirement piece count, batch count or length measurement?
3. What sensor or encoder will provide the pulses?
4. Is the sensor NPN or PNP where applicable?
5. What is the expected pulse or counting speed?
6. Is a preset relay output required?
7. Is an audible indication required?
8. Should the count remain stored after power loss?
9. How should the count reset?
10. What panel size is available?
11. Is one display enough, or are total and batch values needed simultaneously?
12. Has the final model specification been confirmed?

Where Multispan Timers and Counters Are Commonly Used

Industrial timers and counters can be found across many machine automation applications, including:

• Packaging machines
• Filling machines
• Conveyor systems
• Textile machinery
• Printing equipment
• Extrusion lines
• Motor control panels
• Pumps and auxiliary equipment
• Production lines
• OEM machinery
• Batch processing equipment
• Maintenance hour monitoring
• Repetitive machine sequencing

Radical TechMart's timer range includes dedicated products for cyclic, delay, forward reverse, star delta and accumulated time functions, while its Multispan counter offerings include batch and length counting solutions.

Why Buy Multispan Timers and Counters from Radical TechMart?

Radical TechMart lists a broad Multispan timer range including UTR universal timers, cyclic timers, forward reverse timers, delay timers, star delta timers, time totalisers and thumbwheel timers. It also carries Multispan BC Series batch counters and LC Series length counters.

For a useful product inquiry, do not send only:

"Need timer."

or

"Need counter."

Instead, share the actual machine requirement.

For timers, tell us:

• Timing function
• Required time range
• Input or trigger method
• Number of outputs
• Supply voltage
• Mounting requirement

For counters, tell us:

• What needs to be counted
• Sensor or encoder type
• Batch or total count requirement
• Expected counting speed
• Output requirement
• Panel size

This information makes it much easier to narrow down the correct product before comparing individual Multispan models.

Final Thoughts

Timers and counters may look like simple panel instruments, but they solve two fundamentally different automation problems.

A timer answers:

When should something happen?

A counter answers:

How many times has something happened?

Once that difference is clear, product selection becomes much easier.

For a delay, cyclic operation, motor sequence or running hour requirement, begin with the timer function.

For production quantities, batches or material length, begin with the counter and the sensor generating the pulses.

In industrial automation, the correct timer or counter is selected by understanding the machine sequence first and the model number second.

FAQs

1. What is the difference between an industrial timer and a counter?

A timer operates according to elapsed time. A counter operates according to pulses or events. A timer may delay a motor start, while a counter may record how many products passed a sensor.

2. What types of Multispan timers are available?

Radical TechMart lists Multispan universal programmable timers, power OFF delay timers, cyclic timers, forward reverse timers, ON/OFF delay timers, star delta timers, time totalisers and thumbwheel timers.

3. What is a cyclic timer used for?

A cyclic timer repeatedly switches between programmed ON and OFF periods. It can be useful for repetitive machine operations and intermittent equipment control.

4. What is a batch counter?

A batch counter counts individual events while tracking a preset batch quantity. Multispan's BC Series provides separate total and batch displays along with relay and buzzer outputs for batch applications.

5. Can a Multispan counter work with a proximity sensor?

Yes. The BC Series supports compatible PNP/NPN proximity sensors or micro switches, while the LC Series supports proximity or encoder inputs depending on the length counting application.

6. What is a length counter used for?

A length counter converts pulses from an encoder or suitable sensor into material length or speed information. Multispan's LC Series is listed for textile, printing and extrusion applications.

7. When should I use a star delta timer?

Use a star delta timer in a properly designed star delta motor starter circuit where the control system requires timed transition from star to delta operation.

8. Can a machine use both a timer and a counter?

Yes. A packaging machine, for example, may use a counter to detect when the required batch quantity has been reached and a timer to create a delay before the next machine cycle.

A field transmitter can be measuring perfectly, but that measurement is of limited use if nobody can see it, understand it or act when the process moves outside the required condition.

Consider a pressure transmitter installed on a water line. It may be sending a healthy 4 to 20 mA signal, but the operator does not want to read current in milliamps. The operator wants to see the actual pressure in bar.

The same situation appears with tank level, flow, pressure, temperature and many other industrial measurements.

This is where process indicators and process controllers become useful.

Multispan's process control range includes digital process indicators, process controllers, scanners, data loggers, flow totalizers, signal isolators, load cell indicators and jumbo displays. Its process indicator and controller family is designed around configurable industrial analog inputs, with additional options such as alarm outputs, sensor supply, retransmission and RS485 Modbus communication depending on the model.

The challenge is not finding an instrument with a display. The challenge is deciding what needs to happen after the process signal reaches the panel.

What Is a Process Indicator?

A process indicator receives an industrial signal and converts it into a value that an operator can understand.

For example:

Pressure Transmitter → 4 to 20 mA → Process Indicator → 0 to 10 bar displayed

The transmitter generates the electrical signal. The process indicator scales that signal into engineering units.

The same basic idea can be used for:

• Pressure
• Tank level
• Flow
• Temperature
• Analytical measurements
• Speed signals converted into an analog value
• Other compatible process variables

Multispan's PI Series process indicators accept common analog inputs including 4 to 20 mA DC, 0 to 20 mA DC and 0 to 10 V DC. The PI Series is available in several panel sizes, including PI-11, PI-21, PI-38 and PI-41 variants.

This makes the PI range useful when the main requirement is clear local indication of a process signal.

What Is a Process Controller?

A process controller goes one step further.

Instead of only displaying the process value, it can also provide outputs that allow the panel to react when the measured value reaches a configured condition.

For example, a tank level transmitter may send a 4 to 20 mA signal representing 0 to 5 metres.

A process controller can display the level and use relay outputs for functions such as:

• High level alarm
• Low level alarm
• Pump start or stop logic
• Annunciation
• Interlocking with another control circuit

Multispan's PIC-1102 is an example of this type of process controller. It accepts 4 to 20 mA, 0 to 20 mA and 0 to 10 V inputs, provides two relay outputs and includes a 24 V DC transmitter supply. Optional retransmission and RS485 Modbus functions are also available in the process controller family.

The important distinction is therefore simple:

Process indicator: primarily shows the measurement.

Process controller: shows the measurement and can also participate in alarm or control logic.

Indicator or Controller: Which One Do You Actually Need?

A more expensive or feature rich controller is not automatically the better choice.

Start with what the process needs.

Many buyers begin with the question, "Which model should I buy?"

A better first question is, "What must happen after the signal reaches the instrument?"

Start With the Input Signal

Before selecting any process indicator or controller, identify the signal coming from the field.

This is one of the most important selection points.

Common process signals include:

• 4 to 20 mA DC
• 0 to 20 mA DC
• 0 to 10 V DC

The Multispan PI-11, PI-21, PI-38 and PI-41 process indicators support these common analog signal types.

A pressure transmitter with 4 to 20 mA output therefore needs an indicator configured for current input.

A device providing 0 to 10 V output requires the correct voltage input configuration.

Never assume that every process indicator accepts every type of signal.

Why 4 to 20 mA Is Common in Process Monitoring

Many industrial transmitters convert the measured process variable into a standard 4 to 20 mA signal.

For example, a pressure transmitter may be configured as:

4 mA = 0 bar

20 mA = 10 bar

The process indicator receives the current and scales it so the operator sees pressure instead of milliamps.

The same principle can be used for level, flow and other variables.

This is one reason process indicators are versatile. The instrument does not necessarily need to know whether the original measurement is pressure or level. It needs to receive a compatible electrical signal and be scaled correctly.

Scaling the Display Is Just as Important as the Input

Connecting a 4 to 20 mA transmitter is only part of the job.

The indicator also needs to know what that signal represents.

Suppose a level transmitter is configured for a 0 to 6 metre tank.

The display should be scaled so:

4 mA = 0.0 m

20 mA = 6.0 m

Without correct scaling, the electrical signal may be healthy but the displayed process value can still be meaningless.

Multispan's PI Series provides configurable display scaling and selectable decimal resolution for its supported analog inputs.

When replacing an existing indicator, write down both the electrical input and the engineering range before removing the old unit.

When Do You Need Alarm Relay Outputs?

A process indicator tells the operator what is happening.

Sometimes that is enough.

Other applications need an automatic response.

Consider a pressure system where normal operation is below 8 bar. The plant may want a relay to operate when pressure rises above the selected limit.

Or consider a storage tank where the operator needs:

• High level alarm
• Low level alarm
• Pump protection
• Overflow warning

This is when a process controller with relay outputs becomes useful.

The Multispan PIC-1102 provides two relay outputs, allowing it to perform more than simple indication.

Before selecting relay outputs, define exactly what each relay should do.

Do not simply order "two relays" without knowing their purpose.

When Is Built-In Transmitter Supply Useful?

Many field transmitters require a DC supply to operate.

In a conventional panel, this may be provided by a separate industrial power supply.

Some process controllers provide an inbuilt transmitter supply, which can simplify certain installations.

The PIC-1102 includes a 24 V DC transmitter supply.

A typical arrangement may therefore look like:

Process Controller → 24 V Supply to Transmitter → 4 to 20 mA Signal Back to Controller

This can reduce the need for a separate supply in some applications.

However, always confirm transmitter voltage and current requirements before connecting it to an instrument's built in supply.

What Is Retransmission?

Sometimes the process value needs to be visible locally and also sent to another instrument.

For example:

Pressure Transmitter → Process Controller → Local Display

and at the same time:

Process Controller → PLC / Recorder / Another Indicator

An analog retransmission output allows the process value to be passed onward as another analog signal, depending on the instrument configuration.

Multispan lists optional analog retransmission within its process indicator and controller range.

Retransmission can be useful where the plant wants local visibility without losing the ability to send the measurement elsewhere.

Before selecting it, confirm the input required by the receiving equipment.

When Do You Need RS485 Modbus?

RS485 Modbus becomes relevant when the process instrument needs to communicate digitally with an automation system.

Typical connections include:

• PLC
• HMI
• SCADA
• Data acquisition system
• Central monitoring system

Multispan offers optional RS485 Modbus communication on selected process control instruments.

This can be useful when several measurements need to be collected centrally.

But not every process point needs communication.

If the instrument is only being used for local indication, paying for communication may add complexity without providing much benefit.

Plan the communication architecture before ordering the panel instruments.

Panel Size Matters More Than It Looks

Process indicators are available in different front dimensions because every panel does not have the same space or visibility requirement.

Multispan's process indicator family includes several common sizes. For example, PI-11 is 96 × 96 mm, PI-21 is 72 × 72 mm, PI-38 is approximately 48 × 96 mm, and PI-41 is 48 × 48 mm.

A larger display may be useful where operators need easier visibility.

A compact 48 × 48 mm indicator may be more practical in a crowded OEM panel.

For replacement applications, always confirm:

• Front dimensions
• Panel cutout
• Available depth
• Terminal clearance
• Viewing distance

Never replace a process indicator based on front size alone.

Where Signal Isolators Fit

A process indicator and a signal isolator perform different jobs.

The indicator makes the measurement visible.

The isolator is used when the analog signal needs electrical isolation, conditioning or distribution.

For example, the Multispan MI-431 is a DIN rail signal isolator designed for analog signal interfacing. Radical TechMart lists it with single or dual output options, high noise rejection, three way optical isolation and an inbuilt transmitter power supply.

An isolator becomes worth considering when:

• One field signal needs to feed multiple systems
• Ground potential differences create measurement problems
• Electrical noise affects the signal
• PLC and field circuits need additional isolation
• A transmitter needs an isolated signal interface

Do not confuse signal isolation with process indication. They solve different problems.

Practical Example 1: Pressure Monitoring

Suppose you have a pressure transmitter with:

• Range: 0 to 10 bar
• Output: 4 to 20 mA

The requirement is only to show pressure on the control panel.

A process indicator is likely enough.

The setup becomes:

Pressure Transmitter → 4 to 20 mA → Process Indicator → 0 to 10 bar display

There is no need to choose a controller with multiple relay outputs if the plant only wants local monitoring.

Practical Example 2: Tank Level With High and Low Alarms

Now consider a tank level application.

The transmitter provides:

• Range: 0 to 5 metres
• Output: 4 to 20 mA

The plant requires:

• Local level display
• Low level alarm
• High level alarm

In this case, a process controller with relay outputs becomes more appropriate than a display only indicator.

The control concept could be:

Level Transmitter → Process Controller → Local Display + High Alarm + Low Alarm

If the value must also go to SCADA, RS485 communication or retransmission can then become part of the selection.

Practical Example 3: Flow Monitoring With Central PLC

Imagine a flow transmitter connected to a local panel.

The operator wants to see the flow locally, while the central PLC must also receive the measurement.

Possible approaches include:

Flow Transmitter → Process Instrument → Local Display → Retransmission to PLC

or

Flow Transmitter → Process Instrument → RS485 Modbus → PLC

The final choice depends on the control system architecture and what signal the PLC is designed to receive.

This is why communication requirements should be decided before the instruments are purchased.

Common Applications

Multispan process indicators and controllers can be used in applications such as:

• Pressure monitoring
• Tank level indication
• Flow monitoring
• Water treatment plants
• Pump systems
• Utility panels
• Chemical process systems
• HVAC plants
• OEM machinery
• Process skids
• Pharmaceutical plants
• Food and beverage processing
• Industrial production panels
• General process automation

Multispan specifically lists its PI process indicators for pressure, level, flow, temperature, analytical transmitter measurements and analog signals associated with VFD based RPM monitoring.

Common Selection Mistakes

Quick Selection Checklist

Before selecting a Multispan process indicator or controller, confirm:

1. What process parameter needs to be displayed?
2. What signal comes from the field transmitter?
3. Is the input 4 to 20 mA, 0 to 20 mA or 0 to 10 V?
4. What engineering range should appear on the display?
5. What decimal resolution is required?
6. Is indication only required?
7. Are high or low alarms required?
8. How many relay outputs are needed?
9. Does the field transmitter need a 24 V supply?
10. Is analog retransmission required?
11. Is PLC or SCADA communication required?
12. Is RS485 Modbus required?
13. What panel size and cutout are available?
14. What instrument power supply is available?
15. Is signal isolation required?
16. Has the final model been checked against the manufacturer datasheet?

Which Multispan Process Instrument Should You Consider?

Multispan's broader process control family also includes scanners and data loggers, flow totalizers, load cell indicators and jumbo displays, so applications that go beyond a single process point may need a different instrument family.

Why Buy Multispan Process Instruments from Radical TechMart?

Radical TechMart lists Multispan process instrumentation alongside its wider industrial automation range. Its current Multispan listings include PI Series process indicators and MI Series signal isolators, among other process and automation products.

A useful inquiry should not simply say:

"Need process indicator."

Instead, provide:

• Process parameter
• Transmitter output signal
• Engineering display range
• Required alarm outputs
• Supply voltage
• Panel size
• Transmitter supply requirement
• Retransmission requirement
• PLC or SCADA communication requirement
• Existing model, if this is a replacement

These details make it much easier to identify the correct instrument before comparing model numbers.

At Radical TechMart, the useful approach is to start with the process signal and what needs to happen with that signal afterward.

Final Thoughts

Choosing a process indicator or controller becomes much easier when you stop thinking about the display first.

Start with the field signal.

Then ask what the operator needs to see.

After that, decide whether anything needs to happen when the process reaches a particular value.

If only local visibility is required, a process indicator may be sufficient.

If alarms, control outputs, transmitter supply, retransmission or automation system communication are required, move toward a suitable process controller configuration.

The correct instrument is not the one with the most functions.

It is the one that matches the signal, display requirement, control logic and system architecture without adding unnecessary complexity.

FAQs

1. What is a Multispan process indicator?

A Multispan process indicator is a panel instrument used to receive and display compatible industrial analog signals. The PI Series supports common inputs such as 4 to 20 mA, 0 to 20 mA and 0 to 10 V.

2. What is the difference between a process indicator and a process controller?

A process indicator primarily displays the measured value. A process controller can additionally provide relay outputs or other functions so that the panel can react to configured process conditions.

3. Can Multispan process indicators accept a 4 to 20 mA transmitter signal?

Yes. Multispan PI Series process indicators support 4 to 20 mA input along with other analog input options depending on the model.

4. Can a process indicator display pressure, level or flow?

Yes. If the pressure, level or flow transmitter provides a compatible analog output, the process indicator can scale the signal into the corresponding engineering value. Multispan lists pressure, level, flow and temperature among PI Series applications.

5. When should I use a process controller instead of an indicator?

Choose a process controller when you need more than display, such as high or low alarms, relay outputs, transmitter supply, retransmission or communication.

6. What is transmitter supply in a process controller?

Transmitter supply provides DC power for a compatible field transmitter. The Multispan PIC-1102 includes a 24 V DC transmitter supply.

7. Can Multispan process controllers communicate with PLC or SCADA?

Selected Multispan process control instruments provide optional RS485 Modbus communication for integration with compatible PLC, HMI or SCADA systems.

8. What is retransmission in a process indicator or controller?

Retransmission sends a corresponding analog representation of the measured value to another compatible instrument, recorder or control system.

A temperature controller is often purchased when there is a very practical problem to solve.

An oven may not be holding the required temperature. A heater may be overshooting the setpoint. A packaging machine may need more stable heat control. An existing controller may have failed and the maintenance team needs a replacement. In another case, an OEM may be designing a new machine and needs to select the right controller from the beginning.

In each of these situations, starting with a model number is usually not the best approach.

The better method is to first understand the application. You need to know which temperature sensor is being used, the required temperature range, whether PID or ON/OFF control is suitable, how the heater or cooling load will be switched, what panel size is available and whether alarms or communication are required.

Radical TechMart currently lists several Multispan temperature controller families, including compact TC series controllers and multiple UTC universal PID controller variants.

The purpose of this guide is to help you understand what to check before selecting the final Multispan controller.

What Does a Temperature Controller Actually Do?

A temperature controller receives a signal from a temperature sensor, compares the measured temperature with the required setpoint and then operates an output to control heating or cooling.

A typical control loop looks like this:

Temperature Sensor → Temperature Controller → Relay / SSR / Contactor → Heater or Cooling Equipment

For example, consider an industrial oven that needs to operate at 180°C.

The sensor measures the actual oven temperature. The controller compares that reading with the setpoint. Depending on the difference, it decides whether the heating output needs to remain active or reduce its control action.

This is why a temperature controller is not simply a digital display. Its main job is to maintain the process temperature around the desired value.

Start With the Temperature Sensor

The first thing to confirm is the sensor connected to the controller.

This point is often overlooked during replacement purchases. A controller may look physically suitable, but if its input does not match the installed sensor, it will not work correctly.

Common inputs in Multispan temperature controllers include:

• J type thermocouple
• K type thermocouple
• PT100 RTD

For example, the Multispan TC 49P supports J, K or PT100 input options. It also supports PID and ON/OFF control, with relay or SSR control output depending on the configuration.

The Multispan UTC 413P provides selectable J, K and PT100 inputs in a 48 × 48 mm format.

Before ordering a controller, confirm:

• Sensor type
• Required temperature range
• Number of sensor wires where applicable
• Existing wiring
• Sensor polarity for thermocouples
• Whether the controller input is fixed or selectable

If you are replacing an old controller, do not identify the sensor only from the old controller's display. Check the wiring, sensor label or machine documentation if available.

Fixed Input or Universal Input?

Not every application needs a universal temperature controller.

If a machine always uses the same K type thermocouple and the same temperature range, a simpler controller may be perfectly suitable.

A universal controller becomes more useful when the same machine platform may use different sensors, or when the panel builder wants flexibility for different applications.

For example, the UTC 413P allows the user to select J, K or PT100 input and supports PID, time proportional and ON/OFF control.

More advanced Multispan universal controllers support a wider range of sensor inputs and additional control functions. The UTC 4204A M1, for example, supports J, K, R, S and PT100 inputs, along with multiple relay outputs, analog output and RS485 Modbus communication.

The main point is simple.

Do not select a universal controller only because it has more features. Select it when the application genuinely needs that flexibility.

PID or ON/OFF Control?

This is one of the most common questions when selecting a temperature controller.

Both control methods can operate a heating system, but they behave differently.

ON/OFF Control

ON/OFF control is relatively simple.

When the temperature moves beyond the selected switching condition, the controller turns the output ON or OFF.

This type of control can work well where small temperature fluctuations are acceptable and the process does not require very tight temperature regulation.

Typical examples may include simple heating applications where precise temperature stability is not critical.

PID Control

PID control is used when better temperature stability is required.

Instead of only switching fully ON or OFF around the setpoint, PID control adjusts the control action according to how the process is responding.

This helps reduce excessive overshoot and improves temperature stability in many heating applications.

The Multispan TC 49P supports both PID control and ON/OFF control, while the UTC 413P also provides PID, time proportional and ON/OFF modes.

For ovens, furnaces, extrusion machines and other thermal processes where stable temperature is important, PID control is often worth considering.

For a basic switching requirement, ON/OFF control may be sufficient.

The application should decide the control method.

Relay Output or SSR Output?

After selecting the sensor and control method, the next important question is how the controller will operate the load.

Two common choices are relay output and SSR drive output.

Relay Output

A relay output provides physical switching contacts.

Depending on the control circuit, the relay may operate a contactor or another electrical load within its specified rating.

Relay outputs are widely used, but the contacts are mechanical. If the application requires very frequent switching, the switching frequency and relay life should be considered.

SSR Output

An SSR drive output is designed to operate a compatible solid state relay.

This type of output is useful where frequent switching is required, particularly in PID controlled heating systems.

The Multispan TC 49P is available with relay or SSR control output options. Its datasheet lists a relay output and a 12 V DC SSR drive output.

The UTC 413P also provides relay or SSR output options depending on configuration.

One important point should be remembered:

Do not assume the temperature controller should directly switch a large heater.

The heater current, contactor, SSR rating, cable size and protection arrangement should be checked as part of the electrical design.

Check the Panel Size Before Ordering

Panel dimensions become especially important during replacement work.

A controller can have the correct input and output, but if it does not fit the existing panel cutout, installation becomes more difficult.

For example, both the Multispan TC 49P and UTC 413P use a compact 48 × 48 mm front format with a 45 × 45 mm panel cutout.

When replacing an existing controller, check:

• Front dimensions
• Panel cutout
• Depth behind the panel
• Terminal accessibility
• Clearance for wiring

Do not select a replacement controller by front size alone.

The complete electrical specification should also match.

When Do You Need Alarms or Additional Outputs?

A basic application may need only one control output.

Other processes may require more.

For example, an application may need:

• Heating control
• Cooling control
• High temperature alarm
• Low temperature alarm
• Auxiliary relay output
• Analog retransmission
• Communication with PLC or SCADA

The Multispan UTC 4204A M1 is an example of a controller intended for more involved applications. It provides multiple relay outputs, analog output options and RS485 Modbus RTU communication.

A controller like this makes sense when the process genuinely needs these functions.

For a simple heater with one sensor and one control output, a more basic controller may be easier and more economical to use.

Do You Need RS485 Modbus Communication?

Communication should be decided during the panel design stage, not after the controller has already been purchased.

RS485 Modbus can be useful when temperature values or controller settings need to be integrated with:

• PLC
• HMI
• SCADA
• Data acquisition system
• Central monitoring system

The UTC 4204A M1 includes RS485 Modbus RTU communication for PLC or SCADA connectivity.

If the controller will operate independently and nobody needs remote data, communication may not be necessary.

Do not pay for communication simply because it is available.

Where Multispan Temperature Controllers Are Commonly Used

Multispan temperature controllers can be used in a wide range of heating and thermal control applications.

Common examples include:

• Industrial ovens
• Furnaces
• Boilers
• Packaging machinery
• Plastic extrusion equipment
• Injection moulding machines
• Food processing equipment
• Incubators
• Heating systems
• OEM machines
• Industrial control panels

Multispan lists applications such as packaging machinery, extrusion machinery, furnaces, boilers, ovens, incubators and food industry equipment for selected universal temperature controllers.

The exact controller should still be selected according to the individual process requirement.

A Practical Example: Selecting a Controller for an Industrial Oven

Suppose an oven manufacturer says:

"We need a Multispan temperature controller."

That information is not enough.

A more useful requirement would be:

• Sensor: PT100
• Operating range: up to 400°C
• Control requirement: stable heater control
• Output: SSR drive
• Panel size: 48 × 48 mm class
• Power supply: standard industrial AC supply
• Communication: not required

Now the selection becomes much easier.

The engineer can look for a controller that supports PT100, PID control, an SSR drive output and the required panel dimensions.

Now consider a second version of the same oven.

This version needs:

• Heating control
• Cooling control
• High temperature alarm
• PLC communication
• Analog output

The original controller may no longer be sufficient.

A more advanced universal controller may be required.

This is why the application should come first and the model number should come last.

Common Temperature Controller Selection Mistakes

Quick Selection Checklist

Before selecting a Multispan temperature controller, confirm the following:

1. What temperature sensor is being used?
2. What temperature range is required?
3. Is PID or ON/OFF control needed?
4. Is the output relay or SSR?
5. Is the controller being used for heating only or heating and cooling?
6. Are additional alarm outputs required?
7. What panel cutout is available?
8. What supply voltage is available?
9. Is RS485 Modbus communication required?
10. Is analog retransmission required?
11. Is the controller replacing an existing model?
12. Has the final model been checked against the official datasheet?

Which Type of Multispan Controller Should You Consider?

Exact specifications vary between Multispan models and configurations. Always confirm the manufacturer datasheet before final selection.

Why Buy Multispan Temperature Controllers from Radical TechMart?

Radical TechMart lists a broad Multispan range that includes the TC 49P, TC 19 / TC 29 / TC 49 series, UTC 421P and several other UTC universal temperature controller families.

The important part is not simply finding a controller that fits the panel.

A better inquiry includes:

• Sensor type
• Required temperature range
• PID or ON/OFF requirement
• Relay or SSR requirement
• Supply voltage
• Panel dimensions
• Existing controller details, if it is a replacement

With this information, it becomes much easier to narrow down the correct Multispan controller before comparing individual models.

At Radical TechMart, the focus should be on selecting the instrument according to the application rather than only according to the model number.

Final Thoughts

Choosing the right Multispan temperature controller does not have to be complicated.

Start with the process.

Identify the temperature sensor.

Confirm the temperature range.

Decide whether the application needs PID or ON/OFF control.

Check how the heating or cooling load will be switched.

Then confirm the panel size, power supply and any alarm or communication requirements.

Once these points are clear, selecting the controller becomes much easier.

In industrial temperature control, the right controller is not necessarily the one with the most features. It is the one that matches the sensor, process, output circuit and installation requirement correctly.

FAQs

1. How do I choose the right Multispan temperature controller?

Start with the sensor type, temperature range, control method, output type, panel size and power supply. Then check whether your application requires alarms, cooling control, analog output or communication.

2. What is the difference between PID and ON/OFF temperature control?

ON/OFF control switches the output according to the process temperature and setpoint. PID control adjusts the control action according to the process response and can provide more stable temperature control.

3. Can Multispan temperature controllers work with PT100 sensors?

Yes. Several Multispan controllers support PT100 input. Models such as the TC 49P and UTC 413P include PT100 options.

4. Should I choose relay output or SSR output?

The correct choice depends on the load switching arrangement. Relay output uses mechanical contacts, while SSR drive output is used with a compatible solid state relay and is often suitable for frequent switching.

5. What is a universal temperature controller?

A universal temperature controller supports multiple selectable temperature sensor inputs. More advanced universal models may also include additional outputs, analog retransmission and communication.

6. Can a Multispan controller connect to a PLC or SCADA system?

Selected Multispan controllers support RS485 Modbus communication. The UTC 4204A M1, for example, includes RS485 Modbus RTU connectivity.

7. Can I replace my old controller only by matching the panel size?

No. Panel dimensions are only one part of the selection. Sensor input, temperature range, output type, power supply and control function should also be checked.

8. What information should I send when requesting a temperature controller quotation?

Provide the sensor type, temperature range, control requirement, output type, power supply, panel size and existing model number if you are replacing an old controller.

An engineer usually does not start by saying, "I need a Multispan product."

The actual requirement sounds more like this:

"I need to control heater temperature."

"I need a timer for a motor sequence."

"I want to count batches on a machine."

"I need to monitor voltage and current in a three phase panel."

"I need protection against abnormal voltage or current."

That difference matters.

Industrial automation products should be selected according to what the machine or process needs to measure, control, count, time, protect or power. Starting with the model number before understanding the application is one of the easiest ways to select the wrong instrument.

The Multispan range listed by Radical TechMart covers major industrial control categories including temperature controllers, process control instruments, programmable timers, programmable counters, power and energy meters, protection relays and power supplies.

This guide explains where each product family fits and what you should check before finalising a product.

Where Do Multispan Products Fit in an Industrial Panel?

A control panel may contain several instruments, but every instrument has a different job.

A temperature controller may regulate a heater.

A timer may decide when an operation starts or stops.

A counter may monitor production quantity.

An energy meter may show electrical consumption or operating parameters.

A protection relay may react to an abnormal electrical condition.

A signal isolator may help interface one process signal with another part of the control system.

The Radical TechMart Multispan collection reflects this variety, with products such as TC and UTC temperature controllers, UTR and DIN timers, CTR and BC counters, AVF and AVH electrical meters, MPD and VPR protection devices and MI series signal isolators.

The right question is therefore not, "Which Multispan product is best?"

The better question is, "What exactly does my machine or panel need this instrument to do?"

Quick Multispan Product Selection Guide

This simple table should be your starting point before comparing individual models.

1. Multispan Temperature Controllers

Temperature controllers are one of the most common instruments in industrial panels.

They are used wherever temperature needs to be monitored and maintained around a required setpoint. Typical applications may include heaters, ovens, packaging machinery, plastic processing equipment and other temperature controlled machines.

The Radical TechMart Multispan collection currently includes several controller families such as TC-49P, TC-19 / TC-29 / TC-49 variants, PTC and UTC ranges and multiple universal controller configurations.

Before choosing a temperature controller, check:

1. What temperature sensor is being used?
2. What temperature range is required?
3. Do you need simple ON/OFF control or more advanced control?
4. What output will operate the heater or switching device?
5. What panel cutout is available?
6. Is the controller replacing an existing model or being selected for a new machine?

This is where buyers sometimes make a mistake. Two controllers may look nearly identical from the front, but the input, output and control function may be different.

Always start with the sensor and control requirement.

2. Process Control Instruments and Signal Interfaces

Not every process signal needs automatic control. Sometimes the requirement is simply to display, condition or transfer a signal correctly.

The Multispan products listed by Radical TechMart include TI series instruments as well as MI-431, MI-532, MI-631 and MI-632 signal isolator products.

These types of instruments become useful when a panel needs local process indication or when signal interfacing and isolation are part of the system architecture.

Before selection, confirm:

• Input signal
• Required output signal
• Whether electrical isolation is required
• Panel mount or DIN rail installation
• Power supply
• Number of channels
• Connection with the rest of the control system

Do not select a signal interface simply because the input looks correct. The complete input, output and power arrangement needs to match the application.

3. Multispan Programmable Timers

Timers solve a completely different problem.

They are used when something needs to happen according to time.

For example, a machine may need a delay before starting another operation. A motor circuit may need a timed sequence. A process may require repetitive ON and OFF operation.

The Radical TechMart collection includes Multispan DIN 63 timers, UTR series universal timers, DI-22U and SD-22 star delta timer products.

When selecting a timer, ask:

• What timing function is required?
• What is the required time range?
• What starts the timing cycle?
• What should happen after the timing period?
• How many relay outputs are required?
• What supply voltage is available?

The timer should be selected from the sequence first, not from the display size.

4. Multispan Programmable Counters

A timer works with time. A counter works with events, pulses or quantity.

Counters are useful when a machine needs to know how many products have passed, how many operations have occurred, how much length has been processed or when a preset quantity has been reached.

The Radical TechMart Multispan collection includes CTR-63 / CTR-632, LC series length counters and BC series batch counter products.

Before selecting a counter, confirm:

• What exactly needs to be counted?
• Which sensor or pulse source will provide the input?
• Is the requirement total counting, batch counting or length measurement?
• Is a preset output required?
• How should the counter reset?
• Does the operator need one display or multiple values?

In actual machine building, the input device is just as important as the counter itself. A good counter cannot give reliable production information if the sensor arrangement is incorrect.

5. Multispan Power and Energy Meters

Electrical panels increasingly need more information than a basic voltmeter or ammeter can provide.

Depending on the requirement, an industrial meter may be used to monitor electrical parameters or energy consumption at the machine, feeder or panel level.

The Radical TechMart collection lists Multispan products such as AVF-19N, AVF-133, AVF-29T, AVH-14 and AVH-13N.

Before selecting a meter, confirm:

1. Is the system single phase or three phase?
2. Which electrical parameters need to be displayed?
3. Is energy measurement required?
4. Does the installation require a current transformer?
5. What panel space is available?
6. Is the requirement only local indication, or will the information be used elsewhere?

Do not choose an electrical meter simply by the number of values shown on its display. First decide which measurements are actually useful for operation, maintenance and energy monitoring.

6. Multispan Protection Relays

Measurement tells you what is happening.

Protection is about deciding what to do when something goes outside the acceptable condition.

Radical TechMart currently lists multiple Multispan protection products including MPD-13N, MPD-19N, SPP-99, VPR-126, CPR-126, VPR 22-U and SPP-22 / V22-RYB variants.

These products should always be selected according to the exact fault or abnormal condition being monitored.

Before ordering, identify:

• What needs protection?
• What electrical condition needs to be monitored?
• What operating limit is acceptable?
• Is a time delay required?
• What should happen when the abnormal condition is detected?
• How should the system reset after the condition becomes normal?

A protection relay should never be chosen only because its voltage or current rating appears suitable. The protection logic has to match the equipment and control circuit.

7. Industrial Power Supplies

Control panels often contain devices that require a stable DC supply.

That may include instruments, sensors, relays and other automation equipment.

Multispan's category structure on Radical TechMart includes power supplies as one of its industrial automation product families.

When selecting an industrial power supply, check:

• Available input supply
• Required DC output voltage
• Total current required by connected devices
• Future load expansion
• Mounting arrangement
• Panel temperature and ventilation
• Available installation space

Do not calculate the power supply only around one device. Add the complete control load and keep appropriate design margin based on the final system requirement.

Start With the Application, Then Select the Model

A practical selection process looks like this:

Application requirement → Input → Function → Output → Power supply → Mounting → Final model

For example, instead of starting with:

"I need a Multispan controller."

Start with:

"I have a temperature sensor, I need to control a heater, this is my operating range, this is my available panel size and this is what the controller output needs to operate."

That information makes product selection much faster and reduces the possibility of ordering a model that looks right but does not match the actual control circuit.

Common Multispan Product Selection Mistakes

Quick Selection Checklist

Before finalising any Multispan industrial automation product, confirm:

1. What job must the instrument perform?
2. What input signal or sensor will be connected?
3. What output is required?
4. What power supply is available?
5. What panel size or mounting arrangement is available?
6. Does the product need to operate another device?
7. Is it part of a new system or a replacement?
8. What process or electrical range is required?
9. Are any alarm or protection functions needed?
10. Has the final configuration been checked against the product datasheet?

Specifications vary between models and configurations. Final input, output, supply, range, mounting and compatibility should always be confirmed from the relevant datasheet before purchase.

Where Multispan Products Are Commonly Used

Because the range covers control, timing, counting, measurement and protection, Multispan products can fit into many types of industrial systems, including:

• Machine control panels
• OEM equipment
• Packaging machinery
• Heating systems
• Motor control panels
• Production counting systems
• Electrical distribution panels
• Energy monitoring panels
• Process monitoring systems
• Factory automation panels
• Maintenance replacement applications
• System integrator projects

The exact instrument should still be selected according to the individual machine or process requirement.

Why Buy Multispan Products from Radical TechMart?

Radical TechMart lists a broad selection of Multispan industrial automation products across controllers, timers, counters, electrical meters, protection devices and process instruments.

The more important part of industrial purchasing is making sure the product being ordered actually fits the application.

Instead of selecting only from a model number, share the application, existing instrument details, input requirement, output requirement, supply voltage and panel requirement. That information makes it easier to narrow down the suitable product family before comparing individual Multispan models.

Final Thoughts

Multispan covers many of the everyday control and monitoring functions found inside industrial panels, but that does not mean every model is interchangeable.

A temperature controller, timer, counter, meter and protection relay may all sit inside the same panel, yet each one solves a completely different problem.

The safest selection method is simple:

Understand the application first. Confirm the electrical and control requirements second. Select the model last.

That approach makes product comparison easier for engineers, reduces mistakes for purchase teams and helps maintenance departments receive an instrument that actually matches the machine.

FAQs

1. What Multispan products are available for industrial automation?

The Radical TechMart Multispan range covers temperature controllers, process control instruments, programmable timers, programmable counters, power and energy meters, protection relays and power supplies.

2. How do I choose the right Multispan temperature controller?

Start by confirming the temperature sensor, operating range, control requirement, output type, power supply and panel size. Then compare suitable controller models.

3. What is the difference between a timer and a counter?

A timer performs an operation according to time. A counter works according to pulses, events, quantities or similar counting inputs.

4. What is the difference between an electrical meter and a protection relay?

A meter is primarily used to measure or display electrical parameters. A protection relay monitors defined electrical conditions and participates in the protection logic when an abnormal condition occurs.

5. Can I replace an existing panel instrument only by matching its size?

Panel size is only one selection parameter. Input, output, power supply, range, wiring and function should also be checked before replacing an existing instrument.

6. What information should I provide before asking for a Multispan product quotation?

Share the application, required function, input or sensor type, output requirement, supply voltage, measuring or control range, panel size and existing model details if it is a replacement.

A panel builder can select the right sensor, controller and PLC and still face problems during commissioning because the signals between them do not match.

For example, a transmitter may provide a 4 to 20 mA signal while the receiving instrument is configured for voltage input. A controller may support RS485 communication, but the PLC may be using the wrong communication settings. A relay output may be available when the actual requirement is an analog retransmission signal.

In another installation, the controller works perfectly from the front panel, but the SCADA system cannot read the process value.

This is why industrial automation is not only about choosing instruments. It is also about understanding how information moves between the field, the control panel and the supervisory system.

For an iTherm based system, the important questions are simple:

What signal is coming into the instrument?

What output or action is required?

Does the value need to communicate with a PLC, HMI or SCADA system?

Once these questions are clear, product selection becomes much easier.

What Are Industrial Signals, Modbus and I/O?

Industrial signals are the electrical or digital methods used to transfer information between sensors, transmitters, indicators, controllers, PLCs and other automation devices.

In simple words, a field instrument measures something, and a signal carries that information to the next device.

A typical industrial measurement chain may look like this:

Sensor or Transmitter → Indicator or Controller → PLC / HMI / SCADA

The term I/O means input and output.

An input brings information into an instrument.

An output sends information or a control command from the instrument to another device.

The main selection point is not how many features an instrument has. The important point is whether its inputs and outputs match the rest of the control system.

Why Signal Selection Matters in Actual Plant Conditions

This is where many buyers make a mistake.

They select the instrument first and think about the signal requirement later.

A controller may have the correct display size, temperature range and panel dimensions, but that does not automatically mean it has the correct input, control output or communication option.

Consider an OEM machine where the temperature needs to be controlled locally while the PLC also needs to monitor the actual value.

That is different from a stand alone controller that only controls a heater.

Similarly, a pressure transmitter may need to send its measurement to a local process indicator while the same value also needs to reach a PLC or recorder.

The complete signal path should therefore be planned before selecting the final model.

Understanding 4 to 20 mA Industrial Signals

The 4 to 20 mA signal is commonly used in process instrumentation for variables such as pressure, flow, level, temperature and humidity.

Imagine a pressure transmitter measuring 0 to 10 bar.

The transmitter converts that pressure into a corresponding electrical current. A compatible process indicator, controller or PLC analog input receives the current and converts it back into a readable engineering value.

The operator should see pressure in bar, not simply an electrical current value.

Relevant iTherm PI configurations support linear process signals such as 4 to 20 mA, 0 to 20 mA and 0 to 10 VDC, depending on the selected configuration.

A conventional analog signal often makes sense when:

• The PLC already has a compatible analog input.

• Only one process value needs to be transferred.

• The system architecture is already based on analog loops.

• Simple point to point wiring is preferred.

• Digital communication is not required.

What Is RS485 Modbus?

RS485 and Modbus are related terms, but they do not mean exactly the same thing.

RS485 is an electrical communication method used to connect compatible industrial devices.

Modbus RTU is a communication protocol that defines how information is organized and exchanged between those devices.

In practical terms, RS485 Modbus allows compatible controllers and indicators to communicate digitally with PLCs, HMIs, SCADA systems and other automation equipment.

The iTherm source material shows RS485 Modbus communication options in relevant process instrument configurations. It also makes an important point: analog signals and RS485 solve different requirements, so neither should automatically be considered better in every application.

When Does Modbus Make Sense?

Modbus becomes useful when the automation system needs more than a single analog process value.

For example, an OEM may have several controllers inside one machine panel. Instead of treating every controller as an isolated device, compatible instruments can communicate with a PLC or HMI through an RS485 network.

Modbus may be useful when:

• Multiple compatible instruments need to communicate with one PLC.

• Process values need to be displayed on an HMI.

• A SCADA system needs centralized process information.

• An OEM wants machine data available at a common control point.

• The panel architecture is designed around digital communication.

• Reduced point to point signal wiring is desirable.

Communication requirements should ideally be decided during panel design, not after the panel has already been fabricated.

4 to 20 mA or Modbus: Which Should You Select?

There is no universal answer.

The correct choice depends on the system architecture.

For a simple tank level measurement, 4 to 20 mA may be completely sufficient.

For a machine containing several controllers connected to a central PLC and HMI, RS485 Modbus may be more useful.

The decision should be made from the control architecture, not from which technology sounds more advanced.

Where iTherm Process Instruments Fit

Different iTherm process instruments can receive, display, control and communicate process signals depending on the selected model and configuration.

The iTherm PI family is relevant where process values need to be displayed from compatible field signals.

Selected configurations can also provide alarm outputs, transmitter excitation, retransmission and RS485 communication.

The iTherm Fx process controller family goes further when the measured value also needs to control the process.

The available source information describes output options including:

• Relay

• SSR drive

• 4 to 20 mA

• 0 to 10 VDC

Relevant Fx configurations also provide options for alarms, transmitter excitation and RS485 Modbus communication.

This makes the family relevant for applications where the instrument needs to do more than simply display a process value.

What Is Retransmission?

Sometimes a measurement needs to be displayed locally and also sent to another device.

For example:

Pressure Transmitter → Local Process Indicator → PLC or Recorder

The operator may need a local display near the machine, while the plant also wants the same measurement available in the control room.

Retransmission can support this type of architecture.

Selected iTherm PI configurations include retransmission capability as well as communication options.

Before selecting retransmission, confirm what signal the receiving equipment expects.

An analog retransmission output and RS485 Modbus communication should not be treated as the same thing.

Why Transmitter Excitation Matters

Some field transmitters require an electrical supply before they can generate their output signal.

This supply is sometimes provided separately from the panel.

In some instrument configurations, transmitter excitation can be provided by the indicator or controller itself.

Selected iTherm PI universal configurations include transmitter excitation options depending on the exact configuration.

This can simplify certain panel designs, but compatibility must still be checked carefully.

Before using transmitter excitation, confirm:

• Required excitation voltage

• Current requirement

• Transmitter wiring arrangement

• Input signal type

• Instrument model compatibility

Do not assume that every excitation output can power every field transmitter.

Understanding Control Outputs

An industrial controller does more than receive a process signal.

It can also decide what should happen based on that measurement.

For example, a temperature controller may receive a temperature input, compare the value with a setpoint and then operate an output.

Depending on the application and selected controller, the output may be a relay, SSR drive, current output or voltage output.

Each output serves a different purpose.

A relay provides switching.

An SSR drive is intended for compatible solid state relay control.

An analog current or voltage output can provide proportional control to compatible equipment.

Before selecting the controller, always check what the final device actually needs.

Connecting iTherm Instruments with PLC, HMI and SCADA

A common automation architecture may look like this:

Field Sensor → iTherm Controller or Indicator → PLC → HMI / SCADA

But there are several possible variations.

In a simple installation, the instrument may operate independently.

In another application, a process indicator may provide local visibility while retransmitting the measurement to a PLC.

In a larger automation system, several controllers may communicate with the PLC through RS485 Modbus.

The important questions are:

1. What field signal is entering the instrument?
2. Does the instrument need only to display the value?
3. Does it need to control equipment?
4. Are alarm contacts required?
5. Does the PLC need the process value?
6. Is an analog signal or digital communication preferred?
7. Does the HMI or SCADA system need access to the information?
8. Has communication compatibility been confirmed?

Key Selection Factors for Industrial Signals, Modbus & I/O

Before selecting the final iTherm instrument, confirm these points.

Specifications vary between iTherm models and configurations. Final input, output, power supply, communication and excitation details should always be confirmed from the relevant datasheet before ordering. This selection first approach is also consistent with the source guidance, which recommends beginning with the field signal and system requirement rather than only the instrument model.

Common Applications

Industrial signals, Modbus and I/O are relevant across many automation applications, including:

• OEM machine panels

• Temperature control systems

• Pressure monitoring panels

• Flow monitoring systems

• Tank level monitoring

• Industrial ovens and furnaces

• Pharmaceutical machinery

• Food and beverage processing

• Packaging machines

• Water and wastewater plants

• HVAC systems

• Chemical processing

• Utility monitoring panels

• PLC based control systems

• SCADA monitoring systems

Common Mistakes to Avoid

Selecting the instrument before checking the PLC

The controller may work locally but still be incompatible with the PLC input or communication system.

Assuming every model supports Modbus

Communication availability can vary by model and configuration.

Confusing RS485 with Modbus

RS485 describes the communication interface. Modbus defines the communication protocol.

Ignoring communication settings

Correct wiring alone does not guarantee communication. Device address, baud rate and other required settings must match the network design.

Using the wrong analog signal

A current input and voltage input are not interchangeable.

Selecting an output without checking the load

Relay, SSR drive and analog outputs serve different control requirements.

Forgetting transmitter excitation

A field transmitter may require power that must be planned during panel design.

Adding communication after the panel is complete

Late communication requirements can affect wiring, PLC hardware and software development.

Do This, Not That

Quick Selection Checklist

Before selecting an iTherm instrument for an Industrial Signals, Modbus & I/O application, confirm:

1. What process parameter is being measured?
2. What sensor or transmitter is being used?
3. What signal is coming from the field?
4. What input does the iTherm instrument need?
5. Is local indication required?
6. Is automatic control required?
7. What type of output is needed?
8. Are alarm outputs required?
9. Is retransmission needed?
10. Does the PLC require the process value?
11. Is RS485 Modbus communication required?
12. Will an HMI or SCADA system read the information?
13. Does the transmitter require excitation?
14. What panel power supply is available?
15. Has the final configuration been checked against the official datasheet?

Specifications to Confirm Before Purchase

Because this category includes different instrument types and configurations, confirm the following before placing an order:

• Input signal

• Input range

• Sensor compatibility

• Analog input type

• Control output type

• Number of relay outputs

• Alarm configuration

• Retransmission availability

• RS485 Modbus availability

• Communication settings

• Transmitter excitation

• Power supply

• Display size

• Panel cutout

• Operating temperature

• Accuracy

• PLC compatibility

• HMI and SCADA integration requirement

• Exact model and ordering code

Specifications may vary depending on the model and configuration. Please confirm the official datasheet before final selection.

Why Buy iTherm Industrial Signal and Modbus Products from Radical TechMart?

A requirement such as "Modbus controller required" or "4 to 20 mA indicator required" is usually not enough to select the final product.

The complete application should be understood first.

The field input, display requirement, alarms, output type, transmitter power, PLC architecture and communication requirement can all affect the final selection.

At Radical TechMart, the focus is not only to supply the instrument, but to help customers identify the configuration that matches the actual panel and automation requirement.

This is especially useful for OEMs, system integrators, panel builders, EPC contractors, maintenance teams and plant engineers who need to connect instruments with PLC, HMI or SCADA systems.

Final Thoughts

Industrial Signals, Modbus & I/O may look like a communication topic, but in actual projects it is a product selection topic as well.

A controller with the wrong signal can delay commissioning.

A transmitter without the correct receiving input cannot provide useful information.

A Modbus capable instrument will not help if the PLC architecture has not been planned correctly.

And an output that does not match the final control device can create redesign work at the panel stage.

Before selecting an iTherm instrument, always answer three questions:

What signal is coming in?

What needs to happen with that signal?

Where does the information need to go next?

Once those three points are clear, choosing the correct input, output, retransmission or RS485 Modbus configuration becomes much more straightforward.

FAQs

1. What is an industrial I/O signal?

Industrial I/O refers to the input and output signals used by instruments, controllers and PLCs. Inputs receive process information, while outputs send control commands, alarms or process values to other equipment.

2. What is the difference between 4 to 20 mA and Modbus RS485?

A 4 to 20 mA signal represents a process value through analog current. Modbus RS485 provides digital communication between compatible devices. The correct choice depends on the automation architecture.

3. Can iTherm instruments communicate with PLC or SCADA systems?

Selected iTherm PI and Fx configurations provide RS485 Modbus communication options. The exact model and PLC or SCADA compatibility should be confirmed before final selection.

4. Can iTherm process indicators accept 4 to 20 mA signals?

Relevant PI configurations support selectable linear inputs including 4 to 20 mA, 0 to 20 mA and 0 to 10 VDC. Exact model capability should be confirmed before ordering.

5. What is retransmission in a process indicator?

Retransmission allows a measured value received by an indicator to be sent onward to another compatible device, such as a PLC or recorder.

6. What is transmitter excitation?

Transmitter excitation is a supply provided by an instrument to power a compatible field transmitter. Availability and voltage options depend on the selected configuration.

7. Is Modbus better than a 4 to 20 mA signal?

Not automatically. A simple analog measurement may work perfectly with 4 to 20 mA. Modbus becomes more useful when digital communication or multiple networked devices are required.

8. What should I check before ordering an iTherm Modbus instrument?

Confirm the process input, required outputs, power supply, alarms, PLC communication requirement, RS485 Modbus availability, retransmission requirement, transmitter excitation and exact ordering code.

A packaging machine may need to keep a heater ON for ten seconds before moving to the next operation. A conveyor may need to count every product passing a sensor. A winding machine may need to stop after reaching a preset length. Another production line may simply need to record how many cycles were completed during a shift.

All of these are automation problems, but they do not require the same instrument.

Some applications depend on time. Others depend on count. Some need both.

This is where industrial timers, counters and multifunction instruments become useful.

The current Radical TechMart iTherm range includes KTM and XTM timer families, CTR, Cx and XTC multifunction instruments, plus BL counters for batch, length and preset applications.

The official iTherm 2026 catalogue groups these products across programmable digital timers, multifunction counters, timer and counter combinations, and batch or length counters.

The important selection question is not simply, "Which timer should I buy?"

It is, "What event should start the machine action, and what should stop it?"

What Do Timers and Counters Actually Do in Machine Automation?

A timer controls an operation based on time.

A counter controls or monitors an operation based on events or pulses.

For example:

A timer may keep a motor running for 30 seconds.

A counter may stop a conveyor after 100 products have passed a sensor.

A multifunction instrument may combine timing, counting, output switching and memory functions inside one panel device.

This makes these instruments useful in smaller machine automation systems where a full PLC may not be necessary for every timing or counting task.

They are commonly installed in:

Timer or Counter: Which One Do You Need?

The easiest way to decide is to identify what determines the end of the machine operation.

This sounds simple, but many wrong selections happen because the buyer starts with a product series instead of defining the machine sequence.

Where Programmable Digital Timers Fit

A digital timer is useful when machine operation depends primarily on elapsed time.

The iTherm KTM family includes multiple panel sizes and both single row and dual row display configurations. According to the manufacturer catalogue, selected KTM models support programmable up or down timing, two programmable outputs, memory backup, cyclic operation and a broad programmable timing range.

This makes programmable timers useful for functions such as:

The timing function should always be selected around the real machine sequence.

For example, if an exhaust fan must continue running for a fixed period after a machine stops, the required timing logic is different from a machine that needs repeated ON and OFF cycling.

When Pushwheel or Keyboard Setting Matters

The iTherm catalogue includes both pushwheel and keyboard based timer families.

The XTM series is described as programmable digital timers with pushwheel setting. The listed models include XTM-443, XTM-773 and XTM-993.

The KTM range uses keyboard setting for the relevant models.

Radical TechMart also lists the XTM and KTM families within its iTherm timer offering.

The choice between the two should not be based only on appearance.

A pushwheel style can be convenient where operators frequently need direct time setting. A keyboard based unit can make sense where parameters, functions and operating modes need to be configured digitally.

The best choice depends on how often settings change and who will be operating the machine.

Where Multifunction Timers and Counters Make Sense

Some machines cannot be controlled using only elapsed time.

Consider a packaging machine. One function may run for a fixed period, while another must depend on how many packages have passed a sensor.

Using a multifunction instrument can reduce the need for separate timer and counter devices in certain applications.

The iTherm Cx series includes multifunction digital timers and counters. The official catalogue describes selected models with two programmable outputs, programmable memory backup, up or down counting, cyclic timing and universal supply options.

Radical TechMart currently lists Cx-408, Cx-728 and Cx-928 models in this family.

The important advantage is flexibility.

Instead of purchasing a device because it says "multifunction" on the front, first check whether its available modes actually match the sequence required by the machine.

Understanding the CTR Series

The CTR family deserves a little clarification.

Radical TechMart lists it within its multifunction timer and counter range.

However, the official 2026 iTherm catalogue specifically describes the CTR series as multifunction digital time totalisers, counters and RPM indicators. It lists programmable functions for event counting, time totalising and RPM indication.

That makes the series particularly relevant where the machine requirement involves monitoring rather than simple time delay.

Typical examples include:

A production counter and a programmable timer may look similar on a control panel, but the measurement logic is completely different.

Batch, Length and Preset Counting

Counting becomes more application specific when quantity or material length directly controls production.

The iTherm BL Series includes BL-77, BL-886 and BL-99 models on Radical TechMart.

The manufacturer catalogue describes the BL family as multifunction batch, length and preset counters. Selected versions provide two independent outputs, count retention after power failure, programmable batch / length / preset operation and length mode functions.

These functions are useful in applications such as:

For example, a standard event counter may tell you that 500 pulses occurred.

A length counter can use pulse information as part of a configured length measurement process.

That difference matters when selecting the instrument.

Why Sensor Input Matters

A counter does not know that a product has passed by itself.

It needs an input event.

That event may come from equipment such as:

The sensor creates the pulse. The counter interprets it.

This is where buyers often focus too much on the display and not enough on the signal source.

Before selecting a counter, check that the pulse or sensor arrangement is compatible with the selected counter input and the expected counting speed.

For exact input requirements, always use the selected product datasheet rather than assuming all counters accept the same sensor type.

Timers and Counters in Machine Automation

Timers and counters work best when their role inside the machine is clearly defined.

Consider a simple conveyor system.

A sensor detects products.

The counter counts each pulse.

When a preset quantity is reached, an output can trigger another machine action, depending on the selected instrument and control design.

Now consider a heating process.

The controller starts the heater.

A timer determines how long a stage continues.

When the programmed duration is complete, an output changes the next stage of operation.

In both cases, the instrument is performing one clearly defined automation task.

This is why timers and counters remain useful even in factories that also use PLC systems.

A dedicated panel instrument may still be practical for a standalone machine or a clearly isolated timing or counting function.

Key Selection Factors for Industrial Timers and Counters

Before selecting the product, confirm the machine requirement first.

Specifications vary significantly by model, so the final configuration should be checked from the official datasheet before purchase.

Common Mistakes to Avoid

Choosing a timer when the process actually depends on count: Time and quantity are different control conditions.

Ignoring the input sensor: A counter must receive a suitable pulse or contact input.

Selecting only by panel size: Two instruments with the same physical size may provide completely different functions.

Ignoring memory requirements: Some processes need counts or settings retained when power fails.

Not defining reset logic: Decide how and when the count or timer should reset.

Using a basic counter for length control: Length applications may need functions specifically intended for length measurement.

Choosing a multifunction product without checking modes: "Multifunction" does not mean every possible automation function is available.

Ignoring outputs: Know what the timer or counter has to operate after reaching its time or count condition.

Do This, Not That

Quick Selection Checklist

Before selecting an industrial timer or counter, confirm:

1. Is the process controlled by time, count, speed or length?
2. What starts the operation?
3. What stops the operation?
4. Is up or down operation required?
5. Is cyclic operation needed?
6. What sensor or pulse source is being used?
7. How many outputs are required?
8. Does the machine need preset control?
9. Should the value remain stored after power failure?
10. Is a single row or dual row display preferred?
11. What panel cutout is available?
12. What supply voltage is available?
13. Does the machine require batch or length measurement?
14. Has the final model been checked against the datasheet?

Why Buy iTherm Timers and Counters from Radical TechMart?

Radical TechMart lists a broad iTherm range covering KTM and XTM timers, CTR and Cx multifunction instruments, XTC timer / counter products and BL counters.

The useful part of this range is that buyers can select based on the machine task rather than forcing one instrument into every application.

A purchase inquiry saying "digital timer required" is usually not enough.

The correct selection may depend on:

At Radical TechMart, the focus should be on identifying these requirements before finalizing the product.

Final Thoughts

Timers and counters are simple instruments only when the machine logic is already understood.

A timer answers:

How long should this operation continue?

A counter answers:

How many events have occurred?

A batch or preset counter answers:

When has the required quantity been reached?

A time totalizer or RPM indicator answers:

How long has the machine operated, or how fast is it running?

Once that distinction is clear, selecting the right industrial timer or counter becomes much easier.

The correct instrument is not selected only by display size or price. It is selected by understanding the event, timing sequence, sensor signal, output action and final machine requirement.

FAQs

1. What is the difference between an industrial timer and a counter?

A timer operates according to elapsed time. A counter operates according to incoming events or pulses, such as products passing a sensor or machine cycles.

2. What is a programmable digital timer used for?

A programmable timer can control machine operations such as delays, ON and OFF periods, repeated cycles and timed equipment operation.

3. What is a preset counter?

A preset counter compares the accumulated count with a programmed target. Depending on the selected model and machine circuit, its output can be used when the preset value is reached.

4. What is the iTherm CTR Series used for?

The official iTherm catalogue identifies the CTR Series for event counting, time totalising and RPM indication.

5. What is the difference between a standard counter and a batch or length counter?

A standard counter generally counts events. Batch and length counters provide functions intended for quantity based or material length based machine applications.

6. Can timers and counters retain settings after a power failure?

Selected iTherm timer and counter models include programmable memory backup or count retention functions. Exact behaviour should be confirmed for the chosen model.

7. Where are industrial timers and counters commonly used?

They are commonly used in packaging machines, conveyors, textile equipment, production lines, filling systems, winding machines, OEM panels and general machine automation.

8. How do I select the right timer or counter?

Start with the machine function. Confirm whether the process depends on time, event count, RPM, batch quantity or length. Then check the input, outputs, operating mode, display, memory, panel size and supply.