GFI tripping

[Paddy]

Ok. I've got an issue with a GFI breaker triping that feeds an outdoor water garden. I have tried several things that I feel has isolated every link in the system and it still trips...some times. It may go a week just fine or just a few hours.

We have a few GFI breakers for indoor bath rooms. Off one of these GFI breaker circuits, the line feeds the pond pump.

1 I replaced the pump that had worked fine for over a year, still triped
2 Pluged an extension cord into a garage GFI recptical, still triped
3 Changed wires in main breaker panel from GFI #1 to GFI #2, still triped

So the entire original run, breaker/wire/out door recptical and pump have been replaced with new or as with the breaker just switched. The wire being eliminated via an extension cord may not be a good test. The pump is a utility pump used to pump out a wet basement and maybe the small GFI recpt in the garage could not handel the load? So maybe I need to run a new pc of romex to a new recpt by the pond. This is no easy task because the wires are in a wall!

Any ideas?

Patrick T.

 

[Egon]

Could the GFI itself be at fault?

 

[LMTC]

A couple years ago we had problems with one circuit in the house that ran of one of the 5 or 6 GFIs we have. In this case the circuit began by running through a GFI receptacle, rather than a breaker. Eventually I consulted a friend who does som electric work. He explained that they have a spring which gets weak with age. Changed it out, end of problem. Similar problem with a GFI breaker, 20 amp, in the shop. Every few years it goes loony. Install a new one and we're good for a couple years. I've had the circuit checked and no problem was found. Go figure...I never knew they had such a short life span. The breakers have all been Square D too, so not a cheap brand.

 

[Diesel-ME]

I've had to replace trip-happy GFCIs before, but given that you switched breakers that somewhat suggests that it's not the breaker. Could it be that the start-up load of the pump is causing the trip? I had a extra-sized old washing machine on a GFCI breaker once and with a full load the GFCI would almost always trip. It was the initial amperage draw that caused that (or so I concluded at the time).

~paul

 

[jwstewar]

You say it is a small utility pump. Is it rated for continuous duty? Could it just be over heating a causing resistance. We run 2 pumps for our pond. These are both external pumps now.

We were using one submersible, but it started kicking the GFI last year. I replace the GFI outlet and it still did it. We replumbed and went with an external. For some reason I didn't toss the submersible and instead I cleaned it up. It sat out all winter. This spring we took an above ground pool down. I plugged the pump into a GFI outlet and low and behold it work w/o kicking. The pump ran for several ours at Mom & Dad's emptying the pool. Now the pump has been promoted to sitting in the shed.

 

[Bird]

The only time I've had a persistent problem with a GFI breaker and went to buy a new one, the dealer asked me why I needed a new one and said that probably was not the problem. That breaker was for two outdoor receptacles as well as one bathroom. I removed the covers from those two outdoor receptacles and found a few cobwebs in there. I blew them out with my air compressor, put the covers back on, and no more problem. The dealer had told me that just humidity with cobwebs would cause the breaker to kick off.

 

[LMTC]

The dealer had told me that just humidity with cobwebs would cause the breaker to kick off.

I wonder if that's what happens to my brain when it gets humid............the cobwebs get wet and cause it to kick off.

 

[Bird]

I really hadn't thought about it, Wayne, but now that you mention it, I have seen some evidence that I might have that problem myself.

 

[BB_TX]

As I understand GFCI operation (and I could be totally wrong), they have a very sensitive circuit that compares the current in the hot line to the current in the neutral line. If there is difference of more than 3-4 milliamps between the current flowing in and the current flowing out, the GFCI will trip. The idea being that if the two legs are not exactly equal, then current is leaking out somewhere other than where it should (i.e. a ground fault). That would explain how a damp cobweb could cause a fault.
I believe it has nothing to do with overload.

 

[ultrarunner]

To avoid situations of having to trouble shoot entire circuits here at the Hospital... I spec that each required GFCI outlet have it's own GFCI receptacle... That way if there is a problem... no need to go looking for it.

I also use Hospital Grade Hubbel GFCI's... Yes, they cost a lot more.