A sub panel CH 60AMP 3 Pole breaker keeps tripping. I'd like to test the AMPs on the three wires. My clamp tool measures 7.9A while on the 400A AC setting. That seems awfully low to trip a 60 AMP breaker. Is this the right way to measure this kind of wire for this clamp setting?

This is the tester 21050T True RMS 400A AC/DC Clamp Meter.

wire tester reading

  • 9
    You have to measure each wire individually. Combined like you have it the field from the wires tends to cancel each other out.
    – brhans
    Jul 31, 2019 at 16:14

1 Answer 1


No, you have to clamp each wire individually.


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