GFI trips, nothing plugged in

[K6JEK]

I installed a GFI  which trips mysteriously.  It trips with nothing plugged in.  It has a set of connections for daisy chaining and protecting other outlets downstream.  I'm not using them.  Only three wires going in, hot, neutral, ground.  TRIP!  Damn.  So I replaced it.  The new one  trips too.

What's with this haunted house?  Did I just get two defective units or is there something about the AC mains that can trip these things with nothing plugged in? 

[WQ9E]

Does it trip as soon as power is applied?  If so, confirm with your DMM that the black lead truly is "load or hot" since wires sometimes get crossed at junction boxes.

If it trips randomly, does it coincide with your radio operation?  Many of these are RF sensitive.

[WA1GFZ]

Disconnect the breaker and measure resistance between black lead and safety ground. Sounds like you have some leakage/ breakdown.

[K6JEK]

Thanks, guys.

This is at my sister's place.  I'm not operating any radios there but maybe somebody is.  Good suggestions about checking the hot  and hot to ground resistance with the breaker out.

[Pete, WA2CWA]

I had one that would trip under high humidity conditions.

[KE6DF]

I had one go bad on me recently.

All that was plugged in was a coffee pot.

The GFI started clattering -- probably the contacts opening and closing rapidly.

Then it tripped, and smoke came out of the outlet.

I noticed when replacing it that it was a 15a outlet in a 20a kitchen circuit.

Perhaps it was overloaded at some point, but at the time it failed the load was well under 15a.

I replaced it with a 20a GFI outlet and had no further problems.

[N4LTA]

Nothing wrong with connecting two or more 15 amp outlets on a 20 amp branch circuit. That is standard wiring practice.

The only time a 20 ampere rated receptacle is required on a 20 ampere branch circuit is if there is only receptacle.

The NEC only requires having a receptacle rating match the branch circuit rating is if it is a single dedicated receptacle.

[WA3VJB]

I've had them trip on RF, when I transmit using gear on a completely separate branch.

And no, not that much RF, either.

I've also had them trip when I plug in the R390 or R390A.  These receivers bypass the AC line and there's enough leakage that the GFI is correctly responding.

[AJ1G]

We had a GFCI circuit feeding an outdoor post lamp and an exterior grade PVC weatherproof outlet box for plugging in a small garden fish pond pump  that kept tripping without any connected load when turned on for the first time in the spring.  Turned out the outlet box had become a big nest full of gooey apparently conductive ants.....they somehow had gotten into the box and made a real mess.

[N4LTA]

I has an ants nest  in my outdoor disconnect trip a 40 amp two pole breaker (not GFI) at my office HVAC condenser.


Ants must have high conductance

[W1RKW]

Do you really need a GFCI?  We lived with them for years before they became normal practice and lived to talk about it. 

I had one that tripped due to humidity, load or no load. It drove me nuts.  A new replacement did the same thing.  I took it out and said screw it.  When I move I'll replace it with a GFCI to satisfy the policy wonks.

[KA2DZT]

I has an ants nest  in my outdoor disconnect trip a 40 amp two pole breaker (not GFI) at my office HVAC condenser.


Ants must have high conductance

Probably would have never happend if the ants had been wearing their rubber boots.

[N8AFT]

  Ants do make Great Conductors...Too bad they're so small, the orchestra has a hard time following them.
A friend of mine has them on his gas pwd generator, how convenient is that? Same problems. I must agree
we've somehow lived w/o them for decades.. But, We also taught respect & safety around a.c.

[N4LTA]

GFI's save a lot of lives. I have tripped the one in my shop several times with my fat fingers getting acroos the ac line in a chassis.

On concrete, wet locations, and in outdoor situations -  it is not smart to to eliminate them. I know of two cases where people were killed in crawl spaces using power tools and a GFI would have saved them.

The new arf fault breakers are the real PITAs. They detect RF noice generated in an arc and trip. These are now code required in bedrooms and the new NEC expands the requirements.

[WA1GFZ]

I wouldn't remove GFI breakers in a house built after they were required.
You will never collect on an insurance claim power related.
If you have an equipment issue with a GFI just stick an isolation transformer in the line to isolate the breaker from the problem load.

[KE6DF]

Speaking of ants, one time I filled a large bowl with dry catfood for my cats.

But ants got to it before the cats did.

I didn't want to trow it out, so I had the brilliant idea of putting the bowl into the microwave.

I figured that would kill the ants and dead ants would just be more protein for the cats.

Well it didn't work.

All microwaving ants for 2 minutes did was rile them up and they were crawling all around the inside of the microwave when I opened the door.

[KB2WIG]

"  Well it didn't work.  "

Try placing them in the freezer.... that'll stop them. Don't tell the wife, she probably will react like mine did.


klc

[AJ1G]

We lost power in our neighborhood yesterday from about 3PM during a very heavy cloudburst until about 11PM.  I was working late and got home to see the power company trucks getting ready to depart from the pole containing the 8KV neighborhood feed fuse, as the power was then back on.  Just as I pulled up to our house, I saw a big flash around a pole pig up the block and the power was out again.  I hauled down the block and luckily, the crew had not left yet.  They were unaware the power had gone out again and were seconds away from leaving.  I led them to the pole that had flashed, the entire pole was just about covered with a bushy white pine three that had grown up around it over the years.  Some of the upper branches were encroaching on the  8KV high line.   There was some evidence of scorching up there.  Who was/is responsible for keeping the lines and poles clear of tree growth like this?  The particular pole in question is located just off the road in the town's curbside right of way.  The town generally owns several feet of setback along the curbs  here in Stonington. The crew evidently had some suspicion about this pole situation on their initial check, but thought it was OK.

[KB2WIG]

 " Who was/is responsible for keeping the lines and poles clear of tree growth like this? "

The simple answer is "the power company". But, it may be "the phone company". It depends on 'who' owns it. In upstate NY, the phone co was around before there were power companys (companies? companes?). So, 'they' may own more poles than the power utes

klc

[w4bfs]

I has an ants nest  in my outdoor disconnect trip a 40 amp two pole breaker (not GFI) at my office HVAC condenser.


Ants must have high conductance

Probably would have never happend if the ants had been wearing their rubber boots.

no ....they just have low antmittance