HIOKI RM3548 Resistance Meter

A. Product Overview

The HIOKI RM3548 Resistance Meter is a professional portable resistance measuring instrument developed for applications that require precise measurement of very low resistance values.

It is especially useful where ordinary multimeters cannot provide sufficient resolution or accuracy. The RM3548 can measure resistance from microohm levels up to megaohm levels, allowing engineers to inspect electrical connections, windings, conductive joints and other low resistance components.

Key characteristics include:

• Basic measurement accuracy of 0.02%
• Maximum resolution of 0.1 μΩ
• Test current up to 1 A
• Portable design for field and factory use
• Four terminal resistance measurement
• Temperature correction capability
• Internal data storage
• USB communication support
• Suitable for low resistance and winding resistance testing

B. Working Principle

The HIOKI RM3548 uses a four terminal resistance measurement method, commonly known as the Kelvin measurement method.

In conventional two wire resistance measurement, the resistance of the test leads can affect the measurement result. This becomes particularly important when measuring very low resistance values.

The RM3548 separates the current supply terminals from the voltage measurement terminals.

The instrument supplies a known test current through the component being tested and measures the voltage drop across the component separately. The resistance is then calculated using Ohm's Law:

Resistance = Voltage divided by Current

Because the voltage measurement circuit is separated from the current path, the influence of test lead resistance and contact resistance is significantly reduced.

This allows the RM3548 to measure very small resistance values accurately.

C. Why HIOKI RM3548 Is Used

The HIOKI RM3548 is used when accurate resistance measurement is required for checking the quality, condition and reliability of electrical components and connections.

It can be used for:

• Motor winding resistance measurement
• Transformer winding resistance testing
• Cable resistance measurement
• Busbar resistance testing
• Relay and switch contact resistance measurement
• Connector resistance inspection
• Welding joint resistance measurement
• Battery connection resistance testing
• Electric vehicle component testing
• Equipotential bonding resistance testing
• Electrical contact inspection
• Production line quality control
• Preventive maintenance
• Research and development testing

Accurate resistance measurement can help identify loose connections, damaged conductors, poor welds, defective windings and abnormal electrical resistance before they cause equipment failure.

D. Suitable Buyers

The HIOKI RM3548 Resistance Meter is suitable for:

• Electrical engineers
• Maintenance engineers
• Testing laboratories
• Calibration laboratories
• Motor manufacturers
• Motor rewinding companies
• Transformer manufacturers
• Transformer repair companies
• Cable manufacturers
• Electrical panel manufacturers
• Automotive manufacturers
• Electric vehicle manufacturers
• Battery manufacturers
• Industrial maintenance companies
• Electrical contractors
• Research and development laboratories
• Quality control departments
• Production testing departments
• Educational and engineering institutions

Frequently Asked Questions

1. What is the HIOKI RM3548 used for?

The HIOKI RM3548 is used for high precision resistance measurement, particularly very low resistance values found in motor windings, transformers, cables, electrical contacts, welds and electric vehicle components.

2. What is the maximum resolution of HIOKI RM3548?

The HIOKI RM3548 offers a maximum resistance measurement resolution of approximately 0.1 μΩ.

3. What is the basic accuracy of the RM3548?

The HIOKI RM3548 provides basic measurement accuracy of approximately 0.02%, making it suitable for precision industrial measurements.

4. Can HIOKI RM3548 measure motor winding resistance?

Yes. The RM3548 is suitable for measuring motor winding resistance and can be used during manufacturing, servicing and preventive maintenance.

5. Can RM3548 measure transformer winding resistance?

Yes. It can be used for precise resistance measurement of transformer windings and other conductive components.

6. What is four terminal resistance measurement?

Four terminal measurement uses separate terminals for supplying test current and measuring voltage. This minimizes the effect of test lead resistance and improves accuracy when measuring very low resistance.

7. Is the HIOKI RM3548 a microohm meter?

Yes. Because it can measure resistance at microohm levels with resolution as low as 0.1 μΩ, it can be used as a precision microohm meter.

8. What test current does the HIOKI RM3548 provide?

Depending on the selected measurement range, the RM3548 can provide test current up to approximately 1 A.

9. Can HIOKI RM3548 be used for electric vehicle testing?

Yes. It can be used for resistance measurement of electrical connections, bonding points, battery connections and other conductive parts used in electric vehicles.

10. Can it measure cable and busbar resistance?

Yes. The high resolution of the RM3548 makes it suitable for measuring the resistance of cables, wires, busbars and conductive joints.

11. Does the RM3548 support temperature correction?

Yes. Temperature correction can help compensate for changes in conductor resistance caused by temperature variations.

12. Is HIOKI RM3548 suitable for field testing?

Yes. Its portable design makes it suitable for both laboratory measurements and field maintenance applications.

13. What industries use the HIOKI RM3548?

It is commonly used in electrical, automotive, electric vehicle, transformer, motor, cable, battery, electronics, manufacturing and industrial maintenance applications.

14. What is the difference between a normal multimeter and HIOKI RM3548?

A standard multimeter is generally designed for broader electrical measurements and may not provide sufficient resolution for extremely low resistance. The RM3548 is specifically designed for precise low resistance measurement using four terminal measurement technology.

15. Is the HIOKI RM3548 still available?

The original RM3548 has been listed by HIOKI as a discontinued model, with newer models such as the RM3548-50 available as replacement options. Availability of the original RM3548 may depend on existing stock.