GFCI selt test requirement UL 943 standard/ faulting GFCI

[dylanmitchell]

We're a general contractor renovating a home and have an Electrician replacing outlets and switches. He's run into trouble swapping out GFCI's in a garage and outdoor outlet box. The replacement GFCI's he was installing were Hubbell 20 amp self-testing GFCI's that didn't work then Pass Seyour 20 amp self-testing GFCi's that also didn't work. He's coming back later this week to check wiring and grounding.

Anyone else had trouble with installing the new self-testing GFCI's in older properties where existing GFCI's worked fine? The electrician said the GFCI should be testing imbalance in current but a weak ground may cause it to trigger. The existing GFCI's are being replaced for aesthetic reasons with the new Decora style outlets. And yes, this customer cares how his garage outlets look since the garage is more like a shop.

We'll be talking to the customer after getting a report from the Electrician but our bid didn't include replacing wiring or weak grounding so we may have submit a revised bid.

Thanks.

 

[GoldDigger]

The most likely problem when a GFCI receptacle will not reset with no loads connected is a violating connection between neutral and ground. It can find these by injecting a small voltage onto the downstream neutral.

AFAIK some early receptacle units did not include this test.

And of course they will not reset if they have no input power.

Sent from my XT1585 using Tapatalk

 

[dylanmitchell]

Thanks! I'll ask the electrician to check for leakage between neutral and ground by putting current on neutral. Hoping it's in the box or nearby versus him needing to get into the panel or main ground connection.

The most likely problem when a GFCI receptacle will not reset with no loads connected is a violating connection between neutral and ground. It can find these by injecting a small voltage onto the downstream neutral.

AFAIK some early receptacle units did not include this test.

And of course they will not reset if they have no input power.

Sent from my XT1585 using Tapatalk

 

[JFletcher]

We're a general contractor renovating a home and have an Electrician replacing outlets and switches. He's run into trouble swapping out GFCI's in a garage and outdoor outlet box. The replacement GFCI's he was installing were Hubbell 20 amp self-testing GFCI's that didn't work then Pass Seyour 20 amp self-testing GFCi's that also didn't work. He's coming back later this week to check wiring and grounding.

Anyone else had trouble with installing the new self-testing GFCI's in older properties where existing GFCI's worked fine? The electrician said the GFCI should be testing imbalance in current but a weak ground may cause it to trigger. The existing GFCI's are being replaced for aesthetic reasons with the new Decora style outlets. And yes, this customer cares how his garage outlets look since the garage is more like a shop.

We'll be talking to the customer after getting a report from the Electrician but our bid didn't include replacing wiring or weak grounding so we may have submit a revised bid.

Thanks.

My bet is the original GFCIs were miswired line/load or had split conductors (line neutral, hot load on line side terminals). Older GFCIs will still trip and reset under a myriad of miswire conditions, and when they fail, they can fail in a lot of ways.

A weak ground has no bearing because new GFCIs will work perfectly fine on 2 wire circuits (old cloth NM ca 1950s). anything line side of a GFCI, the GFCI doesnt recognize or care about (eta: short of under/overvoltage). the new GFCIs will lockout on miswiring. MWBC being miswired would be my second guess. Third guess is a wet receptacle/wiring causing an actual ground fault downstream from the GFCI. Re-reading your post, that may be the most likely problem.