Clamp-On Current Meter Readings
Got curious with my new clamp-on meter this afternoon. Made the following current readings (one fully charged 24 series battery; converter turned off): .13 amps - parasitic/residual current with e...
Forum Discussion
Matt_Colie wrote:
AZ,
DC current probes are notoriously inaccurate. For starters, they are magnetic field sensitive. I can use mine as a compass and it is one of the best available. They all get real bad at the low ranges.
The reading of 70 amps for a 6.2@120VAC is about right. And, yes, it will toast your little Grp. 24 battery. I am not surprised that inverter put up with it for a while, but that while will be a thermal limit for the hardware.
Matt
I'd say cheap dc current meters may be inaccurate. I have several quality DC/AC true RMS current probes, have designed them as well. A good one needs a "zero" function to null out the surrounding magnetic field field for the hall sensor. and a good amplifier design. Any more a decent accuracy (few %) 150A is obtainable at a reasonable price. And even with 150A + full scale, it's accurate and sensitive enough to make the readings you need down to a few amps or less.
And the good ones are actually pretty insenstive to external fields. Even w/o zeroing, the one I have will only vary at most 0.5A regardless of orientation and surrounding magnetic fields.
but again, it's a case of "you get what you pay for".
