VAX Cluster on Ebay in OK (was Re: More DEC equipment spottedin

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Mon May 3 22:14:44 2004

> 208 is really a 240 volt 3 phase system measured in a star

Is it? I'd assumed it was 120V neutral-phase, which is then 208V phase-phase.

In the UK we get 415V 3-phase, which is 240V (our normal mains voltage)
between each phase and neutral, and 415V between any pair of phases.

> I have not looked at any 3 phase power supplies for computers, but I
> would bet they are 240 volt 4 wire and don't bother with the neutral at
> all, just 3 phases and a ground.

Not at all. A very few PSUs are genuinely 3-phase, and some large disk
drives have 3 phase motors. But in the case of DEC machines at least, the
individual PSUs are single-phase units run between a phase and neutral
(star connected). Of ocurse the load is approximately balanced between
the 3 phases (or it is if the machine is configured properly).

-tony
Received on Mon May 03 2004 - 22:14:44 BST