generator wiring

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sparkfree

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Have a unique situation many someone could help me with. Have a 600 ampsingle phase service 120/240 volt. bld also has a 200 amp 3 phase 3 wire delta 240 volt center phase grounded. we set a 200 amp transfer switch for 3 phase and 600 amp single phase for single phase. generator is 3 phase 120/240 3 phase y output.( we changed taps up to 240 volt). inspector violated because if someone was working on equipment and gen started, center phase would now become hot, we offered to mark all equip with plaques but was rejected. the equipment will run on either 120/240 3 phase or 240 volt to ground or phase without problem. inspector could to me code article I violated. any help?.these problem is only present if gen set is runningotherwise both systems are isolated.
 
Need a better explanation. 2 transfer switches???? One single phase and one 3 phase connected to the same generator and feeding their panels????
 
generator wiring

thanks for getting back to me dennis, there are 2 separate transfer switches one for each service. 1 gen set 120/240 4 wire wye output. the issue the inspector is having is when gen set is running and if someone is working on equipment center phase will now have 120 volt for the 3 phase instead of grounded center phase in a delta system. the equipment just sees 240 volt phase to phase and will run fine. the code in 230 says we can mark voltages but he won't accept. I can't find code article saying we can do this and he can't find one that says we can't.would appreciate any help thanks
 
sparkfree said:
the issue the inspector is having is when gen set is running and if someone is working on equipment center phase will now have 120 volt for the 3 phase instead of grounded center phase in a delta system.

Maybe id labels on all the panels that are delta wired should be identified so if someone read the voltage ratings on the gen set, they would also see at the panel that it is normally fed with the wild leg.
Rick
 
sparkfree said:
already suggested marking all equipment.he wants code article saying its o.k. there isn't one. thanks

This is just a comment and really doesn't help your situiation, but, FWIW it doesn't work that way. You don't have to prove to him it's ok, if he can't cite you an article saying it's NOT ok, then it is OK!
 
use can tap gen set output whatever you want, we tapped 240 instead of 208. unfortunately I got permission from chief electrical inspector who retired. I even called him and he still agreed. but a.h.j. in our area at a last resort can do what they want. I'll see if I can scan diagram somehow,I can barely type. thanks
 
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