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Yesterday, I needed help. I was on a roof of a small commercial building and inspected the HVAC equipment. It was all 208-230v three phase stuff typical for smallish commercial spaces. There was a (full of yellow jackets) Fed Pac, three phase disconnect on the equipment. In the basement, there were three single phase 100 amp disconnects that served panels in the building, and one service panel all fed from a gutter. There was one single-phase disconnect fed from another source with a back-fed 100 amp breaker, two, 2-pole 20-amp breakers and a 2-pole 60 amp breaker. The 60 amp breaker was identified as the breaker for the HVAC equipment. My head started hurting. I then noticed that all the *neutral* wires had been re-identified with black tape. I metered L1 to L2 and got 240v. Then I metered L1 to ground and L2 to ground and each produced 240 v. I called Douglas Hansen; his caller ID must not work and he answered. After I explained the situation, he identified the system as corner grounded three phase. I've read about the configuration- I believe that the breakers used must be rated @ 240v or higher (not 120/240), they must also be rated for 3 phase. §240.85 Is there anything else I should discuss? Clearly, the panel in question is a complete do-over- I see the stuff wrong in this panel, but if I run into another one of these things what should be discussed? Since folks won't be able to resist- the panel and breakers are water damaged, breakers in use not rated for the panel, HVAC breaker should be 50 amps, not 60 and no hold-down kit on the back-fed main. Douglas- thank you for your help, I sincerely appreciate you taking the time to answer my call.