ohms

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Depends. With nothing plugged in and the test button not pushed, somewhere in the vicinity of infinity. With a lamp plugged in an a 100 watt bulb being served, I should think around 144 ohms (120 times 120 divided by 100). With nothing plugged in and the test button pushed, I should think around 2400 ohms (120 volts divided by 5 milliamps).

It would help us if you could be more clear about your questions.
 
Depends upon the conditions.
I just measured one between line and neutral on the line side of the GFCi -measured open cir. (35meg ohms) when the circuit breaker is open.
Push and hold the circuit breaker and it measures 15K ohms!

Load side measured open cir. both ways.
 
ELA said:
Depends upon the conditions.
I just measured one between line and neutral on the line side of the GFCi -measured open cir. (35meg ohms) when the circuit breaker is open.
Push and hold the circuit breaker and it measures 15K ohms!

Load side measured open cir. both ways.
Click to expand...

Some GFCI's have an LED. I assume the thread is
talking about those with no LED.

I recently measured a circuit with GFCIs
with LEDs and got some finite resistance. I don't recall
the exact number - I think it was in the 100's of kilo ohms,
but I can't remember specifically.
 
If you are trying to "test" the gfi receptacle by running an Ohm test on it you are more or less wasting your time. The only reason you will git a reading with the test button pushed is there is a resistor in the gfi between the hot on the test button and the neutral line.
 
charlie b said:
Depends. With nothing plugged in and the test button not pushed, somewhere in the vicinity of infinity. With a lamp plugged in an a 100 watt bulb being served, I should think around 144 ohms (120 times 120 divided by 100). With nothing plugged in and the test button pushed, I should think around 2400 ohms (120 volts divided by 5 milliamps).

It would help us if you could be more clear about your questions.
Click to expand...

I believe with the lamp "cold" you will get a much lower reading because the resistance builds up as the filament gets hot.
 
If the GFCI is not tripped, that is the internal relay contacts are closed, you would read across the internal power supply for the GFCI electronics. I have no idea what that might read.
 
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