I just wanted to share something I recently heard.  A friend was telling me that at a barrel meet he and his wife were at last year, an aquaintance made the comment that his horses would never drink from their water buckets while tied to the trailer.  They would reach for them once or twice, and back away quickly, then not try again.  That sparked a question for my friend, and they quickly discovered the trailer was live, and the horses were getting a shock everytime they reached for their water.

Also last summer, my friend had the disadvantage to witness something much worse.  Another friend had come into some money and splurged on a brand new LQ trailer and new barrel horse.  On her very first trip with both, she arrived at a meet and immediately got the AC and fridge etc running before unloading her horse.  As the horse was stepping out of the trailer, his front feet already on the ground, a hind leg/foot made contact with exposed aluminum (the rubber mats left a small amount exposed between the end of the mats and the beginning of the rubber bumper apparently) and was immediately electrocuted.  The owner was nearly under her horse as she tried to catch him when he began to fall.  He was dead instantly.  As the trailer was new with factory installed LQ she was able to get full insurance on the horse, and have the wiring repaired.  Small consolation I would think.

The result of witnessing two such incidents in such a short amount of time has my friend warning people everywhere he goes (he's a clinician and travels a lot) to please, please, please check your trailer regularly, see if it's live, install a ground rod or something if it's possible, and when in doubt, don't unload or tie your horse to your trailer while it is plugged in to a shore line.

Previous threads on trailer "shock", wiring, shore power, generators, etc....

http://www.horsetrailerworld.com/forum/thread-view.asp?threadid=9767

http://www.horsetrailerworld.com/forum/thread-view.asp?threadid=9324

http://www.horsetrailerworld.com/forum/thread-view.asp?threadid=10533

http://www.horsetrailerworld.com/forum/thread-view.asp?threadid=10473

http://www.horsetrailerworld.com/forum/thread-view.asp?threadid=10652

Everyone should read this one....  http://www.mrtrailer.com/hosspuller.htm

I had a friend lose a really nice Paso Fino gelding exactly that same way.Killed him instantly. It was a horrible thing to see. He touched his face to the side as he was getting out, reared up and fell over dead.

Since that, I will not plug in a trailer with the horses in it. But you brought up a good point of a ground rod or similar...

This happened to a friend of mine this winter he had his generator running his trailer and went to load his horse and shocked his horse.  The horse just flipped over backwards and didn't hurt him but was scary as heck.  So how does a gernerator cause this problem because he said its never happened again after that one time.