How to test current with a clamp meter

A clamp meter can read current in cables; but often a single cable contains multiple conductor wires, conducting electricity to and from equipment. These currents will cancel each other out on the clamp meter and the reading will be zero, so it is important to separate any wires to get an accurate reading. 

Step 1 – Prepare cable 

Ensure the cable to be tested is a single conductor. This may require the removal of the outer layer of insulation to get to the wires within. 

Step 2 – Set meter

Rotate the dial to the amps setting. There may also be a subsequent button to switch between AC and DC.

Step 3 – Clamp wire

Push the button to open the clamp and place it around the wire you are testing, then allow the clamp to close by releasing the button. 

Step 4 – Take reading 

Wait for the value on the screen to stabilise and double check the correct unit is displayed on the screen, then take the number as your reading.