I have a 10/15 hp panel and a 10 hp idler/phase generator motor. I'm in the process of designing a whole new 3 phase system for the shop to replace the multitude of static converters now in use. The 10 hp phase generator data plate says the maximum current draw at full load is 28 amps. To begin with I'll have to add another 100 amp single phase sub panel since all the circuits in the current 200 amp panel are already spoken for. Then I'll have to add a few breakers with one being at least 40 amps to power the phase converter panel and generator. Down stream will be a 3 phase load distribution panel with at least 4 20 amp circuits to power the machines. Add in the wiring, outlets, and 3 phase plugs, etc., etc.
If I purchase all new panels, breakers, wiring, outlets and plugs, etc., etc., the rough cost estimate will be close to $1,000.00 for materials alone. I'm thinking of letting some bids for the project. If I have a contractor do the job I expect the cost to at least double. I would like to do the job myself. I did most of the wiring in our previous house and installed the central air.
The work wasn't hard, but dealing with the inspectors was a nightmare. They don't like to deal with residents doing their own plumbing and electrical work. The minute they "think" they find a problem the inspection comes to a halt. They flag the item and schedule and other inspection 2 weeks down the road. When that item is passed they move to the next. I had a running battle with the electrical inspector over installing a certain brand of disconnect for the AC compressor. Although there was no code stating explicitly a certain brand was to be used he wouldn't pass the inspection until I installed that brand. The worst part was when I toured several other new houses under construction in the same area none of the contractors were using the brand the inspector required me to use. So now I have to decide whether it's more cost effective to hire a contractor, or do battle with the inspectors one more time.