It's been more than 25 years, so my recollection may be hazy, but I think we had 208V 3-phase. I don't recall if it was delta or wye configured, but I tend to think it was the former. CPU from one phase, disk and tape drives from the other and our two big CDC line printers from the third. But as I said, it's been over 25 years since the electricians installed the stuff. We just went by what they recommended. Chuck Yes, our 780 was 208V 3Phase, and I'm PRETTY sure it was 5-wire, so it had a neutral and a ground pin. I think some of the outlets are still in the wall at work, so I'll check the twist-lock to see. I think the power supplies could run off 240 V as well, but possibly the whole machine was slightly different for that option. I know our big data center with IBM 370s was all 208 V also. The multiple H7800 (I think) power supplies each ran off a single phase bridged between two hots, but they were distributed around the phases. The LSI-11 and maybe a few other things ran off 120 V, and I think there was a scope/etc. 120 V outlet there, too. The big cooling blowers were each across two different phases. Some of the larger disk drives had 3-phase motors, and the high-end tape drives (TU-76, TU-77) had 3-phase power supplies and vacuum blower motors. I think the Vax 11/750 was single-phase 220 V, and the 730 was 120 V. Jon