Looks like this is the hot thread on GFCI's this winter which is always the time I get headaches beyond the ordinary because I start to run trough heaters.

Last year I went through agony with stray voltage problems unrelated to the GFCIs. This phenomenon has been around virtually forever but gets worse as buildout continues around us without substantial upgrades in the local grid. (Not ragging on the power company, I think it is a travesty that they have to provide us power in the sticks at the same price as in more densely populated areas. I'd rather be able to pay for a system that works than be stuck in a relationship with them where what they can charge me is limited so they scrape by doing the minimum. Rural electrification was one of those social programs that, if it was ever useful, has long outlived it. But, I digress . . . you better get used it it, that's my middle name.)

So, although I've occasionally seen animals react to trough heaters because of this stray voltage problem, I've been running them for 30 years here and never had trouble tripping GFCIs. (That was why I was doubly mystified by the stray voltage until I realized it was not straying between line and neutral which is the tripping monitor of a GFCI, but rather between neutral and ground.)

But this year, I started plugging in trough heaters in one location and get a loud buzz and then a trip. I'm not sure I have ever heard a GFCI buzz like that. Different GFCI unit from different manufacturer right next to this one on the opposite leg of the 240 connected to the same neutral all on the line side terminals in the box, so I move over and same result. So I plug something else - a hair dryer we keep for thawing stuff - into both of them and it works fine.

So I carry the trough heater to another installation and it works. However the variable is that I have a short (6 foot) extension cord in the location that keeps tripping. I didn't suspect the cord because it doesn't trip with just the cord plugged in, but I plugged the hair dryer into the cord and that causes a trip. So I go back and move the trough closer and low and behold, the thing works without the cord. Cord looks fine and dry, uncut, not old or cracked, but assume this means there is maybe a moisture related minor neutral to ground fault that isn't noticed until there is actually current flowing. This makes sense as I think about it, although not when yours frustrated truly was out in the field.

Now my wife reports that the sans extension cord installation tripped the breaker overnight, so I'm slogging out there momentarily. Not to undermine her logic skills but she infers this from some lights being off rather than from having taken a flashlight and actually checking the kill-o-watt that I keep installed at the trough heater so that we can monitor hours that its on, know that it is working and know if the power is out visually.

It may be that I left one of the other circuits off with all our testing yesterday and that is why the lights are off. But I'll fill in that blank in a half hour. Meantime, I think I have managed to talk myself through what is happening with the extension cord just in writing this out.

I guess the bottom line is, could we get a less sensitive GFCI that would provide some protection in these circumstances but eliminate this constant nuisance tripping in difficult circumstances. There were trough heaters long before their were GFCI, and maybe I don't spend enough time on farm forums, and/or maybe all the old timers with stories of dead cattle, horses and farmers killed by trough heaters gone critical just haven't made the net, but the cost benefit of this safety protection is starting to exceed its utility at the moment.

My other notion is just to try an airstone for a pond and see if that will keep the water open, but thats maybe a more appropriate discussion for a livestock forum, but figured a bunch of handy guys around here might have dealt with other stuff besides wire in their lives -- not that there's anything wrong with that . . . .


thanks,

brian