No Trip of GFCI

[carle3]

Seems to be the topic of the month for me.

I have a GFCI receptical that tests as being grounded and having correct polarity with a GB GFCI tester.

The GFCI receptical will not trip when using the GB GFCI-tester but will trip on the recepticals own test button.

Is this a bad GFCI, or a poor ground that is causing a faulty test on my GFCI-Tester?

In the past I have always marked this as a faulty GFCI receptical. But in knowing how the GFCI-tester uses the equipment grounding conductor to create a fault I am now questioning if I am wrong here.

[Richard Moore]

Carl,

I use a Suretest, but same thing. I've had them trip with the test button, but then fail with the GFCI tester. I remember one that would take 4½ seconds to trip with the suretest, time after time, but tripped immediately with the test button.

Bottom line...If it's grounded, and assuming your tester works normally on other GFCIs, then something is off. For the price of a new GFCI I don't think anyone is going to fault you for saying it needs replacing. Better safe than guessing!

[kurt]

Hitting the button on the device is fine; it's approved by the mfg., and it's the best test.

Honestly, I forget why; this has been hammered out so many times on so many threads, I pushed the details out of my head and simply remember the test button part. Maybe someone else can elaborate more intelligently.

What's most important is using the proper terminology. "Mash the button" is the correct phrasology.

Mash the button. Mash. Repeat after me; mash.

[carle3]

Kurt,

hmmm...mash...gooood.....

reminds me of the old song...The Monster Mash...god help me it is getting late

I did try a search on tripped or non tripping of GFCI's prior to posting this and came up empty but I am sure it not the first go around on this.

[Jim Katen]

I have a GFCI receptical that tests as being grounded and having correct polarity with a GB GFCI tester.

The GFCI receptical will not trip when using the GB GFCI-tester but will trip on the recepticals own test button.

Is this a bad GFCI, or a poor ground that is causing a faulty test on my GFCI-Tester?

In the past I have always marked this as a faulty GFCI receptical. But in knowing how the GFCI-tester uses the equipment grounding conductor to create a fault I am now questioning if I am wrong here.

Is this an older GFCI?

If so, you might have found a bootleg ground.

- Jim Katen, Oregon

[Chad Fabry]

Line/ load reversed? When you tripped the gfci w/ the test button, did the power go off?

[carle3]

Hi Jim,

No, this is a condo unit from 2000. But not having a Sure Test I am unable to check for a boot leg ground (short of taking it apart).

I didn't know if the amount of current that the tester faults to ground may not be sufficiant enough to trip this paticular GFCI yet since the receptical trips on its internal test it is still good and within manufactures specifications. I did use 2 different testers just to verify my equipment.

[Scottpat]

The best method for testing a GFCI outlet is by mashing the button on the unit. I do not use the nightlight testers. I seldom use my SureTest. I use a voltage sniffer and a two prong neon light tester (forgot the name, they cost about $4).

Douglass Hansen did a session a few years back on the problems with the three prong testers and SureTest testers. It was an eye opener.

[Jim Katen]

Hi Jim,

No, this is a condo unit from 2000. But not having a Sure Test I am unable to check for a boot leg ground (short of taking it apart).

I didn't know if the amount of current that the tester faults to ground may not be sufficiant enough to trip this paticular GFCI yet since the receptical trips on its internal test it is still good and within manufactures specifications. I did use 2 different testers just to verify my equipment.

The onboard tester is diverting a small amount of current through a resistor to test the GFCI. If the GFCI trips when the onboard tester is pushed, it means that the GFCI device is working properly.

The hand-held tester diverts a small amount of power to ground to test the GFCI. If the GFCI device is working properly and if the GFCI doesn't trip when the hand-held tester is pushed, it means that either the tester is defective or the grounding path that it's attempting to use is defective.

From our discussion so far, I'm fairly certain that there's a high impedance connection somewhere in the grounding path from that receptacle. If an electrician troubleshoots this, I'll bet you a dollar that he finds a loose grounding connection somewhere on that circuit.

- Jim Katen, Oregon

[Chad Fabry]

Seems to be the topic of the month for me.

I have a GFCI receptical that tests as being grounded and having correct polarity with a GB GFCI tester.

The GFCI receptical will not trip when using the GB GFCI-tester but will trip on the recepticals own test button.

Is this a bad GFCI, or a poor ground that is causing a faulty test on my GFCI-Tester?

In the past I have always marked this as a faulty GFCI receptacle. But in knowing how the GFCI-tester uses the equipment grounding conductor to create a fault I am now questioning if I am wrong here.

As I said before, this is the classic symptom of a GFCI that has been incorrectly wired with the line going to the load side of the GFCI.

Even though the GFCI trips from its own button, the power to the receptacle is not interrupted.

[Scottpat]

Good reason to use a voltage sniffer after you trip one of the older GFCI outlets. I can't tell you how many I have found with power after they have been tripped.

[Neal Lewis]

Chad, reread the original question; they are two separate "classic symptoms".

[carle3]

Hi Chad....sorry....I did not mean to ignore your evaluation....I was missing one piece of the puzzle....when tripped the power is cut.

I think Jim has it right....I have been miss interpreting this as a defective GFCI receptical and it is really a fault in the equipment grounding conductor for this circuit. I just did not know if it may have been a limitation of the tester that could also create this.

[StevenT]

I'll bet you fifty cents that Chad is on the money.

There may be an additional ground problem. But, I believe that reversing the line/load will result it breakin manually but not with tester/line problem

[Chad Fabry]

Chad, reread the original question; they are two separate "classic symptoms".

Indeed, indeed two symptoms there are.

Hi Chad....sorry....I did not mean to ignore your evaluation....I was missing one piece of the puzzle....when tripped the power is cut.

That changes things.