I'm not sure I follow...where is the problem? If the generator is only feeding 2 phases to the panel, the panel operates at 120/208. The panel is rated for 120/240. The third phase never leaves the load side of the breaker at the generator. The only thing I wondered about when first seeing this setup was how the imbalanced electrical load (2 phases out of 3) would affect the mechanical load on the diesel engine.
We provide all of our sites with temporary panels, and they're always 120/240. This GC bought a new generator and for some reason decided to buy a 3 phase model, although I can't figure out why. I think what happened here is that the temp panel was already built and on-site when the new genny showed up...our guy went to the site and just connected the cable from the panel to the new unit.
If you think there may be issues with this setup I would really like to know what concerns you so I can prevent any further problems.
