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Posted By: smokumchevy Possible stray current in water trough - 11/25/06 05:05 AM
Since I intalled CSA rated trough heaters, designed for this particular fibreglass impregnated plastic water trough two of the horses have not been drinking water, leading me to believe that they must be experiencing some stray current somehow in the water since the customer mentioned he thought that the water might be too warm and stuck his finger in the trough (idiot, lol)but it was fine and after asking him if he got a lift or tingle he said no.

Any troubleshooting tips or suggestions before I head out their tomorrow afternoon??

My plan of action tomorrow is to test voltage to ground, voltage to neutral, neutral to ground and ground to a different sourced ground (3prong ext cord to the house power). Then test for voltage on the stainless steel backing of the element mount to ground and to neutal for any strange readings.

As a last resort, I'll drain the trough and remove the heater element to check for voltage on the outer shell of the element.

This is a new 60A sub at the barn from the house splitter to a disco fused at 60 A with a run of 190ft of 3 wire #4 WMU direct burial. It lands on a Cuttler Hammer 100A 24 circuit panel with its own groundplate and bonded. The bare ground in the panel feeder was well taped at both ends and isolated from any contact in this installation.

From the barn panel I ran a 3-12 direct burial (60ft) to a postbox for a merc vapour light and tied the second cicuit to an existing (about 15ft) 2-14 direct burial to a gfi plug (which I did test with a gfi plug trip tester and metered to grnd and to neutral, and ground to neutral with good readings) on a post behind a wooden wall dividing the watertrough and the post.

The trough heater is a 3 prong plug cord for outdoor use with a sealed unit at the heater end that screws into the plastic trough via a plastic clamping nut and gasket.

The whole property is pure sand as far as you can dig.

Thks in advance,
Greg
Posted By: e57 Re: Possible stray current in water trough - 11/25/06 07:59 AM
Animals are a lot more sensitive to things as are we.... To say voltage - much more so, and they don't wear boots.

Found some interesting sites on this...
this is from one of them
Quote
~installation of an equipotential plane and voltage ramp is highly recommended. An equipotential plane is created when the reinforcing steel in the concrete floor is electrically bonded to all metal equipment~
http://www.bae.umn.edu/extens/aeu/aeu2.html

And a possibly interesting book , with possibly some good advise on equipotential planes suitable for the purpose for those who work around farms...

FYI I am not one of them.... But would suggest the use of a very sensitive meter for checking point to point contact. A wiggy won't cut it. But as suggested by that page about cows - maybe they just don't like or trust the new fangled heated water thingy.
You can lead a horse to water...
Posted By: gfretwell Re: Possible stray current in water trough - 11/25/06 05:58 PM
My only point of reference is swimming pools but the principle is the same. Maybe you should try to create a local ground reference with a small ground ring around the tub. I don't think I would go for the full grid in 680.26 but a buried wire around the tub would be a start. It may be too late for these horses tho. They may already associate the tub with the shock and not go back.
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