Years back I did a resi with 600 amp, 120/208, 3 phase. It was a mansion back then, not Mc; 3 phase loads were AC, and pool pumps. Yes, the POCO had a $$$ for the install and the monthly fees were high, but the owner did not care.
The big issue was 'does the conduit come in any clors, along with the 'big gray box' (CT cabinet)???
THere is one resi in the Twp I work in that has OLD 3 phase, delta, for an extinct machine shop.
