Re: FREE TO A GOOD HOME

From: Michael Moroney (moroney_at_world.std.spaamtrap.com)
Date: 05/24/03 

Date: Sat, 24 May 2003 02:44:53 +0000 (UTC)

Chris Olive <nospam@raytheon.com> writes:

>Huh... could have sworn a 750 ran on 3-phase... 8-/

Not the 750 itself, but some old disk drives of that era apparently did.
A long-time Deccie was telling me just today about these drives with
three phase drive motors.. wouldn't even spin on single phase.

One model was smart enough to not spin if the phasing was reversed,
the other would spin _backwards_ (but was smart enough not to load the
heads). Forget which drives those were.

DEC always overbuilt everything power-related in those days. Probably
lots of 750s came with 3 phase 30+A power cords even though they could
actually be powered off a single phase 15A home circuit. Look in the
old hardware, most of those mega power feeds went to a controller with
a bunch of ordinary single phase outlets, and all the subcomponents of
the computer were plugged into those outlets.

-Mike

Relevant Pages

  • Re: My first attempt in 3phase with a VFD
    ... > single phase or not. ... (If you can find the toshiba drives website (tic something, ... It will start your motor by itself, ... The best way is with a 240 volt Variac. ...
    (rec.woodworking)
  • Re: Two inverter drive questions
    ... Second, more trivial, the specified speed control pot is 2.5K. ... I don't have the main manual for the inverter, ... Drives do not like frequent power cycles. ... Supply is Single phase via a 3-phase rotary converter, ...
    (uk.rec.models.engineering)
  • Re: FREE TO A GOOD HOME
    ... but some old disk drives of that era apparently did. ... One model was smart enough to not spin if the phasing was reversed, ... actually be powered off a single phase 15A home circuit. ...
    (comp.os.vms)
  • Re: My first attempt in 3phase with a VFD
    ... single phase or not. ... (If you can find the toshiba drives website (tic something, ... It will start your motor by itself, ... Often manuals don't say whether you can run single phase, ...
    (rec.woodworking)
  • Re: Two inverter drive questions
    ... where the motor is running all the time the lathe is in use. ... Second, more trivial, the specified speed control pot is 2.5K. ... Drives do not like frequent power cycles. ... Supply is Single phase via a 3-phase rotary converter, ...
    (uk.rec.models.engineering)