Can a clamp meter measure DC?
A clamp ammeter is a specialized instrument for measuring alternating current. Its front-end is a current transformer. It achieves measurement tasks through the principle of electromagnetic induction.
Clamp on ammeter cannot test direct current because direct current does not have an alternating magnetic field, so no secondary current is generated in clamp on transformers. Therefore, clamp on ammeter cannot measure direct current.
Clamp on ammeter is generally used to test AC current. It is made based on the principle of AC eddy current, similar to a transformer, and obtains signals through electromagnetic induction. I usually use DC ammeters in series with circuits, but theoretically, it is possible to make a DC clamp meter. The method of measuring DC current with a clamp ammeter that can be used for both AC and DC is similar to the method of measuring AC current with an AC clamp ammeter. Select the appropriate range, insert a wire to test the current into the center of the clamp, and the corresponding current will be displayed on the screen.
How to measure resistance with a clamp ammeter
① Turn the switch to the appropriate resistance range.
② Keep the switch in the open position.
③ Connect the red probe to the "Ω" terminal and the black probe to the "COM" terminal.
④ Connect the red and black probes to both ends of the tested wire. When measuring the resistance of the wire in use, the power supply should be disconnected first, and the capacitance connected to the wire should be fully discharged before measuring.
Wire continuity test
① Turn the switch to the 200 Ω (or buzzer) position.
② Connect the red and black probes to the "Ω" and "COM" terminals respectively.
③ If the resistance between the red and black probes is less than (50 ± 25) Ω, the built-in buzzer will beep.
