Test a low-voltage motor winding
Insulation tester (megger)
Look for: A 500 V or 1000 V range and a readable scale into the gigaohm region.
Selection guide
Which instrument for which job
Start from the job you need to do. Each row names the instrument type, what to look for, and links to the guide, calculator and standard behind it.
Insulation and earthing
Trend an HT motor, generator or transformer
Motor-operated insulation tester
Look for: A 2.5 kV or 5 kV range and steady motor-driven voltage for 10-minute PI readings.
Test house or office wiring
Digital insulation tester
Look for: A 500 V range, a guard-free simple layout and a clear digital reading.
Test a long cable or submersible pump motor
Insulation tester
Look for: Enough range for long-cable leakage and a rugged, field-friendly body.
Check an earth pit
Earth tester
Look for: A range matched to your target resistance and enough spike cable for the layout.
Measure soil resistivity before designing an earth grid
Four-terminal earth tester
Look for: Four terminals for the Wenner method and a low range with fine resolution.
Check busbar joints, contacts and bonding
Micro-ohm meter
Look for: A high test current, four-wire (Kelvin) leads and a milli-ohm or micro-ohm range.
Test transformer oil
Oil BDV test set
Look for: An adjustable electrode gap, a suitable voltage range and a clear trip indication.
Withstand test on HV equipment
HV test set
Look for: The rated test voltage, a duty cycle that suits your test time and proper interlocks.
Commission a protection relay
Relay test set
Look for: Current and voltage range for your relays, single or three phase, and timing accuracy.
Electrical and power
Check phase sequence before connecting a motor
Phase sequence indicator
Look for: A simple, visible indication and a voltage range for your supply.
Measure current without opening the circuit
Clamp meter
Look for: True RMS, enough jaw opening for your cable or busbar, and the right CAT rating.
Find small leakage currents
Leakage clamp meter
Look for: A milliamp-level range and resolution on a clamp that can enclose both conductors.
Measure DC current in a solar or battery system
DC-capable clamp meter
Look for: DC current measurement, not just AC, and a CAT rating for the system voltage.
Check a three-phase motor for imbalance
Clamp meter
Look for: True RMS and a stable reading on each phase in turn.
General troubleshooting: voltage, continuity, resistance
Digital multimeter
Look for: True RMS, the right CAT rating, a continuity buzzer and enough digits for your work.
Electronics bench
Look at a waveform
Oscilloscope
Look for: Bandwidth well above your signal, enough sample rate and the right channel count.
Generate a test signal
Function generator
Look for: The waveforms and frequency range you need, and amplitude and offset control.
Measure an inductor, capacitor or resistor
LCR meter
Look for: Test frequencies that match the part, and basic accuracy for your tolerance.
Power a circuit on the bench
DC power supply
Look for: Voltage and current rating with headroom, adjustable current limit and low ripple.
Test a battery or power supply under load
DC electronic load
Look for: Voltage, current and power rating above the source, plus the CC, CV, CR and CP modes you need.
Process and environment
Check or simulate a 4-20 mA loop
Process calibrator
Look for: Source and measure for mA, V and the sensor types you use.
Check lighting levels
Lux meter
Look for: A range covering your spaces and a sensor with good cosine response.
Measure workplace noise
Sound level meter
Look for: A-weighting, a suitable dB range and fast and slow time weighting.
Measure air flow
Anemometer
Look for: A velocity range for your ducts or vents, and a way to log or hold readings.
Measure temperature
Digital thermometer
Look for: The sensor type, range and probe style for your process.
These are general selection pointers, not a substitute for your specification. Confirm ranges and ratings against the datasheet, or send us the job and we will confirm the right model.
Not sure which one fits your job?
Tell us what you are testing and the voltage or range involved. We will point you to the right model.