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Jack Wingo
05-02-2011, 09:32 AM
Recently, had a GFCI receptacle that tripped when the 'Test Button' was pushed, however, using a Sure Test or a Sperry tester, in that receptacle and other receptacles down current, the breaker would not trip. Which test is accurate, the handheld testers or the test button.
I do recall at a Florida Association of Bldg Inspectors meeting, we had a Leviton rep, give a presentation and he said the builtin test button was an accurate indicator.
As always I would appreciate your assistance.

Jim Port
05-02-2011, 09:49 AM
The only recognized test is using the built-in test button.

Jim Robinson
05-02-2011, 10:51 AM
Possible non-grounded GFCI? That will do exactly what you said happened.

Eric Barker
05-02-2011, 01:54 PM
The various manufacturers of GFCI devices (whether breakers, receptacles or after-market testers) have varying thresholds for tripping. When you use your own GFCI tester on a GFCI protected receptacle you may likely not be comparing apples to apples.

Jerry Peck
05-02-2011, 03:57 PM
Jack,

As the others have said - the TEST button is the best test for the GFCI tripping.

The GFCI should trip at 5 ma +/- 1 ma, so the various levels of tripping should be no less than 4 ma and no greater than 6 ma. The cheaper testers typically only have a single test current of greater than 6 ma (where all should trip), the more expensive testers typically start out with a low test current which slowly gets higher until 7 ma to 10 ma (some used to go higher, but there was no need, if the GFCI does not trip at 7 ma the GFCI is defective).

The reason the GFCI did not trip at a downstream receptacle could be many, from a poor to no ground, to wiring the GFCI receptacle as a bypass instead of a pass-through, and other possible causes.

John Kogel
05-02-2011, 03:59 PM
I've seen GFCI's with hot and neutral reversed, the test button still trips it, the 3 prong tester won't trip it, but it would of course indicate the wiring was wrong.

Sometimes outdoor units can be really slow to respond to the plug in tester, probably due to tarnished slots, poor contacts.

Lou Romano
05-02-2011, 04:47 PM
Possible non-grounded GFCI? That will do exactly what you said happened.

Jim nailed the more likely problem here!

Ted Menelly
05-02-2011, 05:19 PM
Jim nailed the more likely problem here!

Dido .... but I usually do not agree with babies sticking a plug into a receptacle :confused:

H.G. Watson, Sr.
05-02-2011, 11:06 PM
Recently, had a GFCI receptacle that tripped when the 'Test Button' was pushed, however, using a Sure Test or a Sperry tester, in that receptacle and other receptacles down current, the breaker would not trip. Which test is accurate, the handheld testers or the test button.
I do recall at a Florida Association of Bldg Inspectors meeting, we had a Leviton rep, give a presentation and he said the builtin test button was an accurate indicator.
As always I would appreciate your assistance.

I agree with Jim Robinson, however in reading your post I had this thought: "Breaker? what breaker would not trip?"

Its also possible the GFCI receptacle is older and/or has failed after too many trips or exposure to voltage gradients, and will not open under fault conditions.

Links to short but informative historical articles you may find interesting:

Replacing 2-Wire Ungrounded Receptacles (http://ecmweb.com/mag/electric_replacing_wire_ungrounded/index.html)

Three-Lamp Circuit Tester: Valid Tester or Night-Light? (http://ecmweb.com/mag/electric_threelamp_circuit_tester/)

Think like a GFCI (http://ecmweb.com/mag/electric_think_gfci/index.html)

You should also read the instructions and limitations of your "tester", presuming it is listed.

Lou Romano
05-03-2011, 04:15 AM
Enjoyed the links HG thank you!

Randy Aldering
05-03-2011, 07:37 AM
Jerry's post brings up an important consideration: know your test equipment. Most three-lamp GFCI testers will trip any GFCI that is properly wired and properly grounded. But this should be verified on a known outlet occasionally, to verify that the tester is functioning as designed. If the internal test button trips the GFCI, then it will probably trip in a fault condition. There is a "real-life" test, but I will not go into it here, and do not recommend it.

Lou Romano
05-03-2011, 09:58 AM
If you take a standard voltage tester, like a Wiggy or similar and test the outlet from hot to ground it will trip if it is grounded and working properly. Obviously this does not mean the GFCI trips at the acceptable ma range but it does tell you if it is grounded and that it will at least trip.

I have found that if the device trips by test button and or testing hot to ground it is usually working properly when verified with my GFCI tester.