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	Subject - Sub Service Goof Electricman Heres a good one.....I was finishing up a new dwelling today with the last thing to do, hook up an existing horse barn sub panel some 75 ft away from the new house. So I go on down to the barn to have a look see at how the sparky before me hooked everything up ya know make sure grounded correctly and all. So I take the dead front off and WHOA the first thing I notice is this guy has a #8 thwn conductor goin from the phase A lug to a ground rod pounded into the dirt floor of the barn. Upon further investigation this guy before me(notice I am no longer callin him an electrician) has the ground and neutral bonded together, so I go get the homeowner and ask did you use this barn lately ? answer yes up until the new construction on my house started. I ask circuit breaker trip to barn? answer No. Hmmmmmmm Did you have really high electric bills? answer Yes. iwire Obviously a wire from a phase conductor to the earth is a major problem. That aside the panel must have a grounding electrode system connected to the grounding terminals. The panel also might have to have the neutrals and grounding bonded. A couple of questions. Did the feeder from the main service have an equipment grounding conductor? Are there any continuous metallic paths bonded to the grounding system in both buildings or structures involved? The NEC allows a separate building or structure to use the neutral as the grounding means if you meet the requirements of 250.32(B)(2) lctrc789 Maybe he thought this was a corner grounded DELTA system, one phase is grounded and at 0 volts to ground , but 480 volts phases to phase LOL I also would let him know that this barn does contain livestock and this is all together a different ball game, I know many who say article 250-32 (b)2 is "IF' you do it this way, But I always use that article as a NEW SERVICE installation only. My first choice is always 250-32 (b)1. for a sub panel because of the fault current path you could get otherwise. Because he does have livestock (horses) in there you should read article 547-8 a and you will see that this is a different field of grounding. I have done some cattle barns and hog houses and large horse barns, this is a different game all together. I would highly recommend you check this out it could be an animal gets a severe shock if not grounded properly, and even kill it. Many rural locals have their own set of guidelines for livestock here we require a 4 wire system (if single phase) grounding conductor and a separated neutral and ground bar. as well as a 8 ft minimum ground rod with the proper size grounding conductor to the grond bar. Electricman Answers to iwire, Yes there was and is now a seperate EGC run from the main service (4 wire). And no there is not a metallic path from the main structure. Thanks also to Pat for his input journeyman491us Electricman?? Did you ask the homeownerif the horse ever acted strange?? If the hot leg were grounded like that she should consider herself lucky!!! Animals are very susecptible to stray currents, and as a previous post has stated, wiring for "barns" is a whole different ballgame. Things like "equi-potential ground planes" come into play. A hot ground rod could wreak havoc! ...Taking the cover off and "seeing what the last guy did" was wise on your part. Never trust "the last guy!" Electricman Never asked about strange animal going ons or anything, But it was one of those you can walk away from and feel good about.