A pressure gauge is one of the simplest instruments in a plant, but it is also one of the easiest to select incorrectly.

A maintenance team may ask for a 0 to 10 bar gauge with a bottom connection. That sounds complete, but it still leaves several important questions unanswered. What is the process media? Is the line vibrating? What process temperature will the gauge see? Is the pressure only a few hundred millibar? How far away will the operator read the dial?

These details decide whether you need a compact stainless steel Bourdon gauge, a larger industrial gauge for easier reading, or a capsule gauge specifically meant for low-pressure measurement.

Baumer offers different pressure gauge constructions for these requirements. The ADC and ADD models use an all stainless steel Bourdon measuring system, while the AXD, AXF and AXH models use a capsule measuring element with copper alloy wetted parts for low-pressure applications.

The right way to select between them is not by model number alone. Start with the application.

What Are Industrial Pressure Gauges?

Industrial pressure gauges provide a direct local indication of pressure at a machine, pipeline or process point.

You will commonly find them on:

• Pumps
• Compressors
• Hydraulic systems
• Refrigeration equipment
• Process lines
• Chemical equipment
• Utility skids
• Diesel engines
• Food processing equipment
• Pharmaceutical equipment

Unlike a pressure transmitter, a mechanical pressure gauge does not normally send an electrical signal to a PLC or SCADA system. Its main job is to give operators and maintenance teams an immediate pressure reading directly at the equipment.

This makes the gauge useful for startup checks, troubleshooting, preventive maintenance and routine operator rounds.

Bourdon Pressure Gauge or Capsule Pressure Gauge?

This is the first major selection decision.

Choose a Bourdon gauge when:

You are measuring normal industrial pressure on pumps, compressors, hydraulic systems, process lines or machinery.

Baumer ADC and ADD use a Bourdon measuring system with AISI 316L stainless steel for the socket and Bourdon element. Their standard construction is designed for demanding industrial pressure measurement.

Choose a capsule gauge when:

The pressure is very low and a conventional industrial pressure gauge is not the best fit.

The Baumer AX series is designed for low-pressure measurement. Available pressure ranges start from 25 mbar and extend to 600 mbar. Typical applications include clean air, gases, draft measurement and low-viscosity, non-corrosive media.

That means a pump discharge pressure point and a low-pressure air duct may both need a gauge, but they should not automatically use the same type.

Baumer Industrial Pressure Gauge Models

Baumer ADC All Stainless Steel Pressure Gauge

The Baumer ADC is a practical option when you need a compact pressure gauge for industrial machinery, pumps or equipment where installation space is limited.

Its 50 mm dial keeps the overall size small, while the stainless steel measuring system makes it suitable for industrial pressure applications where material compatibility matters.

The standard 50 mm version has an accuracy of ±2.5% of full scale. If the application requires easier reading or better accuracy, moving to the 63 mm ADD version may make more sense.

Technical points to note:

• Nominal size: 50 mm
• Measuring principle: Bourdon
• Accuracy: ±2.5% of full scale
• Case and bezel: AISI 304 stainless steel
• Socket: AISI 316L stainless steel
• Bourdon element: AISI 316L stainless steel
• Movement: AISI 304 stainless steel
• Standard protection: IP65
• Ambient temperature: -25°C to +65°C
• Standard process temperature: maximum 200°C
• Operating pressure: 75% of scale value

Where it is commonly used:

• Pumps
• Engine compressors
• Diesel engines
• Hydraulic systems
• Refrigeration equipment
• OEM machinery

Baumer ADD All Stainless Steel Pressure Gauge

The Baumer ADD is a better fit when you still want a compact industrial gauge but need a larger 63 mm dial and improved reading accuracy.

In practical maintenance work, the difference between a 50 mm and 63 mm dial can matter. Gauges are often installed below eye level, inside machinery or next to pumps and piping. Better dial visibility makes routine inspection easier.

The model can also be configured as a dry, fillable or glycerine-filled gauge depending on the installation condition.

For machinery with vibration or pressure pulsation, a liquid-filled configuration may improve pointer stability and reduce mechanical wear.

Technical points to note:

• Nominal size: 63 mm
• Measuring principle: Bourdon
• Accuracy: ±1.6% of full scale
• Case and bezel: AISI 304 stainless steel
• Socket and Bourdon: AISI 316L stainless steel
• Standard protection: IP65
• Optional IP66 and IP67 protection listed
• Standard process temperature: maximum 200°C
• Dry, fillable and glycerine-filled configurations available
• Multiple bottom-entry and back-entry mounting arrangements available

Where it is commonly used:

• Process pumps
• Compressor systems
• Hydraulic equipment
• Petrochemical plants
• Pharmaceutical equipment
• Food and beverage processes

Baumer AXD Capsule Pressure Gauge

The Baumer AXD is intended for applications where pressure is too low for the normal selection logic used with a Bourdon gauge.

With a 63 mm nominal size and capsule measuring element, it is well suited to compact low-pressure indication points.

Technical points to note:

• Nominal size: 63 mm
• Measuring principle: Capsule
• Accuracy: ±1.6% of full scale
• Case and bezel: AISI 304 stainless steel
• Capsule: Copper alloy
• Socket: Copper alloy
• Movement: Copper alloy
• Standard protection: IP55
• Ambient temperature: -25°C to +65°C
• Process temperature: maximum 100°C
• Operating pressure: 75% of scale value
• Zero adjustment provision

Where it is commonly used:

• Clean air pressure measurement
• Gas pressure indication
• Draft measurement
• Food processing equipment
• Pharmaceutical utilities
• Low-pressure process systems

Baumer AXF Capsule Pressure Gauge

AXF uses the same basic capsule pressure measuring concept as the AXD but increases the dial size to 100 mm.

That larger dial becomes useful when the pressure point is mounted farther away from the operator or when small pressure changes need to be read more comfortably.

The AX series supports multiple pressure, vacuum and compound scales, including units such as mbar, kPa, inWC, MWC, inHg and mmHg depending on the requirement.

Technical points to note:

• Nominal size: 100 mm
• Capsule measuring element
• Accuracy: ±1.6% of full scale
• AISI 304 stainless steel case
• Copper alloy capsule and socket
• IP55 protection
• Zero adjustment provision
• Maximum process temperature: 100°C
• Multiple bottom-entry, back-entry and flange mounting arrangements available

Where it is commonly used:

• Low-pressure utility systems
• Clean air lines
• Gas pressure monitoring
• Draft indication
• Food and beverage plants
• Pharmaceutical utilities

Baumer AXH Capsule Pressure Gauge

The Baumer AXH takes the same low-pressure capsule concept into a 150 mm nominal-size gauge.

This is useful when local pressure needs to be visible from a greater distance or when operators need a large, easy-to-read dial.

AXH retains the low-pressure capsule design, copper alloy measuring system and ±1.6% full-scale accuracy of the AX family.

Technical points to note:

• Nominal size: 150 mm
• Measuring principle: Capsule
• Accuracy: ±1.6% of full scale
• Stainless steel case and ring
• Copper alloy capsule
• Copper alloy socket
• IP55 protection
• Maximum process temperature: 100°C
• Zero adjustment provision
• Multiple mounting configurations available

Where it is commonly used:

• Plant utility systems
• Large process equipment
• Clean gas lines
• Draft measurement
• Low-pressure monitoring stations
• Applications requiring easy long-distance reading

ADC vs ADD vs AXD vs AXF vs AXH

Key Selection Factors for Industrial Pressure Gauges

1. Start with the actual pressure range

Do not select a gauge whose maximum scale is almost equal to normal operating pressure.

For the AD series, the recommended continuous operating pressure is 75% of the scale value. The gauge also has defined overpressure limits depending on the selected pressure range.

Give the gauge enough headroom for normal process variation.

2. Check whether the pressure is genuinely low

If the requirement is measured in tens or hundreds of millibar, a capsule gauge may be more appropriate than a standard Bourdon gauge.

This is where AXD, AXF and AXH become relevant.

3. Match the wetted material to the media

ADC and ADD use AISI 316L stainless steel for the socket and Bourdon element.

AX models use copper alloy for the capsule and socket.

That difference should be treated as a selection parameter, not just a construction detail.

4. Decide the dial size from viewing distance

A 50 mm dial works well on compact machines.

A 63 mm dial provides a useful balance between size and readability.

For low-pressure applications, 100 mm and 150 mm AX variants become useful when the gauge must be read from farther away.

5. Consider vibration and pulsation

A pump or compressor can produce a pointer that continuously fluctuates.

Where required, consider a liquid-filled configuration or suitable accessories such as a snubber. This helps stabilize the pressure indication under pulsating conditions.

6. Confirm process temperature

Do not check only ambient temperature.

The fluid entering the pressure connection can expose the gauge to much higher temperatures. For high-temperature services, accessories such as siphons or cooling elements may also need to be considered.

7. Confirm mounting and connection before ordering

Bottom entry, lower back entry, center back entry, flange mounting and bracket mounting are not interchangeable once the installation is fabricated.

The connection size and thread standard also need to match the process connection.

Common Mistakes to Avoid

Quick Selection Checklist

Before ordering an industrial pressure gauge, confirm:

1. What is the normal operating pressure?
2. What is the maximum possible pressure?
3. Is it pressure, vacuum or compound measurement?
4. Is the application low pressure?
5. What process media touches the gauge?
6. Are stainless steel wetted parts required?
7. What is the process temperature?
8. Is there vibration or pulsation?
9. What dial size can the operator read comfortably?
10. Is bottom or back entry required?
11. What is the thread and connection size?
12. Is a calibration certificate required?
13. Are IP66, IP67 or other protection options needed?
14. Is an accessory such as a snubber, siphon or gauge cock required?

Why Buy Industrial Pressure Gauges from Radical TechMart?

Pressure gauge selection becomes much easier when the inquiry includes the actual process details rather than only a model number.

At Radical TechMart, the focus is to help customers select pressure instruments according to application, measuring range, media, material, mounting and installation condition.

Support is available for OEMs, maintenance teams, factories, EPC contractors, project engineers and purchase departments looking for Baumer pressure gauges and other industrial pressure instruments.

If you are replacing an existing gauge, sharing the old model number, pressure range, connection, dial size and application can help narrow down the suitable replacement much faster.

Final Thoughts

The difference between ADC, ADD, AXD, AXF and AXH is not simply dial size.

ADC and ADD are better suited to conventional industrial pressure measurement using an all stainless steel Bourdon measuring system. AXD, AXF and AXH move into low-pressure measurement using a capsule mechanism, with dial size increasing according to the visibility requirement.

The best pressure gauge is the one that matches the process pressure, media, operating temperature, mounting arrangement and the way the maintenance team will actually use it.

In industrial applications, correct pressure gauge selection saves much more than the cost of replacing a wrong instrument. It makes daily inspection easier, reduces premature failure and gives operators a pressure reading they can actually trust.

FAQs

1. What is the difference between Baumer ADC and ADD pressure gauges?

Both use an all stainless steel Bourdon measuring system. ADC is the 50 mm version with ±2.5% full-scale accuracy, while ADD is the 63 mm version with ±1.6% full-scale accuracy and better dial readability.

2. When should I use a capsule pressure gauge?

A capsule gauge is useful for low-pressure applications such as clean air, gas and draft measurement. The Baumer AX range is designed for low pressures from 25 mbar to 600 mbar.

3. What is the difference between AXD, AXF and AXH?

The main difference is nominal dial size. AXD is 63 mm, AXF is 100 mm and AXH is 150 mm. Larger dial sizes are useful when the gauge needs to be read from farther away.

4. Can Baumer industrial pressure gauges be glycerine filled?

The AD series includes dry, fillable and glycerine-filled configuration options. Liquid filling can be useful where vibration or pulsation affects pointer stability.

5. Can these pressure gauges connect directly to PLC or SCADA?

These are mechanical pressure gauges intended primarily for local pressure indication. For electrical signal transmission to a PLC, HMI or SCADA system, consider a pressure transmitter or an appropriate electronic pressure instrument.

6. How do I choose the correct pressure gauge range?

Select a range that keeps normal operating pressure comfortably below full scale. Also consider startup pressure, process fluctuations and possible pressure spikes before finalizing the range.

7. Is stainless steel construction always necessary?

Not always. It depends on process media, environment and application. However, wetted-part compatibility should always be checked. A stainless steel case alone does not mean the internal measuring parts are stainless steel.

8. What details should I provide when asking for a pressure gauge quotation?

Provide pressure range, media, dial size, process connection, mounting type, process temperature, required accuracy, dry or filled preference and any calibration requirement.