Tech Tips

How accurate is your Inductive amp probe?

  Image above is parasitic draw, my ET 332 shows 32mA, 
low amp probe (left) shows 107mA, 100A range on
my fluke shows 54ma. According to fluke, the 90i-610s,
is good at 1A and above, the PDA low amp probe is
supposed to be good to 50mA. The Fluke 80i-110s
($750) goes down to 100mA.

I plugged in the underhood lamp, draw went to 339mA,
PDA shows 413mA, fluke shows 372mA, a little closer.

Opened the door to add courtesy lamps, draw now at 1035mA,
PDA at 1290mA, fluke at 1520mA, way off here,These probes
are mainly for looking at waveforms, not for measuring low
amps draw, use your meter to get an accurate reading in mA's.