I really intended to state the following conditions they (the event) are distributing 240V power comprised of 2 - 120V legs "A" and "B" from the service which has a neutral "C" , so it's probably a 120/240V 4 wire delta single phase. At the distribution junction #5 pull box that they have connected in the vendor service distribution box,, there's only 2 - 120V legs and a ground that run back to the main. It is strictly intended to operate 240V load only no neutral is present or required for that purpose. However they went in my opinion a little " Old school" by being able to derive 120V branch circuits for the vendor connection by using the Ground , thereby energizing the ground back to the neutral / ground bond at the main panel. There's no separate ground in the distribution, no ground rod, no transformer in the distribution box creating it's own neutral. I had to change my 4 wire L14-30P plug (30Amp 125/250V rated 3P 4 wire) out to a three wire L6-30P (30Amp 250V 3P 3 wire) eliminating the ground and connecting the neutral wire to the ground screw on the plug, essentially cheating my panel inside the trailer to think that it's getting 2 120V branch feeds, which it is but my contention and question is "IS THIS SAFE"? and if not how many specific NEC violations have just been committed? Please site specific code article to win the booby prize.
Thanks ,
sorry for the confusion on the first pass and for potentially the second
In reading the above, heres is what could happen:
since you no longer have the EGC from the trailer that is connected to a path back to the neutral there is no fault current path to operate a breaker in the event of a fault, even if you were to install a ground rod it would not allow enough current to open a breaker, so now as it is if anything in your trailer were to fault to ground your whole trailer would become hot or 120 volts to earth, this could injure or kill someone maybe a child who might be barefoot, there is no way I would leave this as it is, as you could be accountable and be possibly found partly at fault if something should occur!!!
The second thing that could happen is the loss of the neutral/EGC, now you have a floating neutral problem, since the neutral maintains the 120 volts between the 240 volt hots, it can no longer do this so you end up with two series 120 volt circuits across 240 volts, if one side of this has a heavier load the voltage on that side will decrease but the other side will increase, so one side might have 40 volts and the other side will have 200 volts, something will burn up and it could get expensive, but loosing the neutral is always a possibility in all wiring systems but there is a side item that was mentioned but because you didn't bond the EGC from the trailer to the neutral in the receptacle then it is of little value, but what they were talking about is if you would have bonded the EGC so there was a fault path for shorts, then if you lost the neutral since the trailer and everything is bonded to this EGC the voltage drop on the neutral would have also been on all that is bonded to the EGC and again the above first part of this post would apply as you would not only have a voltage problem and damage would happen but you would also have had a dangerous shock hazard.
Sorry for such a long post but I'm trying to convey how dangerous this is, and if this is an event where children will be at, let me ask this would you want to live with the idea that this could kill a child!!!, you need to get something done, even if it takes going to the state, wiring like this is dangerous and needs to be stopped!!!!
I'm not aiming the above at you as it is the ones running the event who is cheap ping out on doing this the right way and the city for not inspecting it to make sure it gets done right.
