How do you check your GFCI outlets?

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Dave85

Dave85

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I used to use the plug in tester with the 3 lights and press the tripper button on that until I was working with one guy and day and he said that I should stop using that tripper button.

I asked why and he explained that one day an inspector told him that the plug in testers short between the hot and neutral pins as where the Ideal voltage/continuity testers with the two lead wires can trip between the hot and ground pins.

From that day on I have been tripping them with my Ideal tester between the hot the ground.

What method does everyone else here use and what is the proper way to trip a GFCI?
 
I use plug-in testers. I trip the gfci with the button on the tester, reset, and trip it with the test button on the gfci inself. Isn't the button on a gfci-test plugin tester designed to test gfcis? Every inspector I ever saw uses one.
 
Dave,
I asked why and he explained that one day an inspector told him that the plug in testers short between the hot and neutral pins...
Click to expand...
A hot to neutral short will not cause the GFCI device to open the circuit. It will cause the OCPD to open the circuit. The same applies to a hot to ground short...GFCI testers use a current limiting resitor to bring the hot to ground current down near the trip range of the GFCI, 5mA.
Don
 
Dave85 said:
I asked why and he explained that one day an inspector told him that the plug in testers short between the hot and neutral pins as where the Ideal voltage/continuity testers with the two lead wires can trip between the hot and ground pins.
Click to expand...
The plug-in tester button connects a resistor between the receptacle hot and the receptacle EGC. No EGC, no trip.
 
Took one apart once, and found a 20K resistor inside. Connecting that across the hot and ground leads causes a 6 mA current to leak, tripping out a properly wired and functioning GFCI unit.
 
Usually I just grab the nearest faucet, a fork, and an apprentice....

Fortunately, they've all worked so far.
 
If the GFCI test button connects (through a resisitor) from the hot to the ground, how is it they work when there is no ground present?

I always thought they tested from the hot (after it passed through the CT) to the neutral (before it passed through the CT) to cause the current imbalance.
 
hardworkingstiff said:
If the GFCI test button connects (through a resisitor) from the hot to the ground, how is it they work when there is no ground present?

I always thought they tested from the hot (after it passed through the CT) to the neutral (before it passed through the CT) to cause the current imbalance.
Click to expand...
You have it exactly correct. Plug-in testers don't work when there's no EGC present.

The plug-in doesn't have access to the neutral ahead of the CT, so it has to use the EGC. I guess you could say that using the EGC is closer to mimicing an accidental personnel ground contact than using the neutral is.
 
how gfi's work

how gfi's work

To first determine the best way to test a gfi is to first understand how it works. We now go to Kirkoff's law. In english says "what goes in must come out.
With a GFI this relation is messured between hot and neutral
5 amps being used (hot) 5 amps going out (neutral) reason for the 0 reading
When you have a "short" that trips the gfi. the fault is with the ground.
therefore, say, 15 amps being used (hot) and none going out (Neutral)
the inbalance causes the gfi to trip.
It's the same reason a gfi will not reset when you have a broken neutral.
You have have power, but it is not carried on the neutral.
again, the load is not balanced. IE: -0-

So going to ground and hot is the only way to test a gfi or loose a neutral.
the Gfi will always trip.

remember Kirkoff's law..... what goes in..... must come out.......
 
hardworkingstiff said:
If the GFCI test button connects (through a resisitor) from the hot to the ground, how is it they work when there is no ground present?

I always thought they tested from the hot (after it passed through the CT) to the neutral (before it passed through the CT) to cause the current imbalance.
Click to expand...
The test switch on the GFCI unit operates its internal mechanism, and will work whether you have an EGC or not. The test switch on a plug-in tester only works on what I previously termed properly wired outlets, which assumes the presence of an EGC.

While you are permitted to use GFCIs as replacements on non-grounded circuits, you will have to soley rely on its built-in test switch to ensure the internal mechanism is functioning.

Or you could use a 100 foot extension cord, and a Vol-Con or Wiggy tester, testing from the hot of your outlet to the "ground" in the extension cord....
 
From what I understand, the only approved way (by the manufacturers) to test a GFI is to use the test button on the device or breaker. Using the plug in testers just a few times will supposedly damage the device.

That's what Joe Ross told us at a seminar, and he toured the country giving seminars on behalf of the manufacturers.
 
I would like to know the rationale that Joe Ross used. It seems to me that when using the plug-in tester, the contacts are only interrupting 4 to 6mA.

I can't think of problems what a few times would cause, especially given the low current it is interrupting.
 
j_erickson said:
From what I understand, the only approved way (by the manufacturers) to test a GFI is to use the test button on the device or breaker. Using the plug in testers just a few times will supposedly damage the device.

That's what Joe Ross told us at a seminar, and he toured the country giving seminars on behalf of the manufacturers.
Click to expand...

There is no way that having a 6 mA ground fault as the testers create is going to cause the GFCI to fail.

I have heard that on real ground faults (L-G) that the GFCI contacts can fail either open or closed. Supposedly they are designed to allow the BC breaker to trip first in such a case.
 
j_erickson said:
From what I understand, the only approved way (by the manufacturers) to test a GFI is to use the test button on the device or breaker. Using the plug in testers just a few times will supposedly damage the device.

That's what Joe Ross told us at a seminar, and he toured the country giving seminars on behalf of the manufacturers.
Click to expand...

If this is true, then everytime someone gets a call about a tripped GFCI receptacle, they better change it.
 
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