Originally Posted by rurak
That is most certainly a 120/208 volt 3 phase four wire 42 circuit panel.
Don't mean to argue but clearly it is not 3 phase the middle lead is clearly a neutral and you have 2 110v legs. Now those could be coming in from a 3 phase box not in the picture. What do you think is running on 3 phase power there?
We have 3 phase power running into our shop at the mines to be able to run some of our underground machines in there when we are working on them. Like a continuous miner or a roof bolter. Our air compressor is 3 phase but every thing else is single phase. We run a delta-wye configuration on our transformer and use a center tap to obtain our ground. Our miners run on 995 volt and our roof bolsters run on 480 volt our coal haulers are 240volt dc battery powered that in converted to ac because ac motors are easier to control and last longer