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Path: utzoo!utcs!lsuc!pesnta!hplabs!hpda!fortune!wdl1!jbn
From: jbn@wdl1.UUCP
Newsgroups: net.micro
Subject: Re: Voltage protection for micros
Message-ID: <278@wdl1.UUCP>
Date: Thu, 14-Feb-85 01:14:53 EST
Article-I.D.: wdl1.278
Posted: Thu Feb 14 01:14:53 1985
Date-Received: Fri, 15-Feb-85 02:10:59 EST
Sender: notes@wdl1.UUCP
Organization: Ford Aerospace, Western Development Laboratories
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Nf-ID: #R:brl-tgr:-815900:wdl1:1400032:000:982
Nf-From: wdl1!jbn    Feb 13 18:32:00 1985


     There's nothing wrong with that idea; there is commercial gear for
that purpose, but it tends to be on the large side and noisy.  Some years
ago I worked at a Univac mainframe site which had such a rig; the MG set
was a vertical-spindle unit about 3' in diameter and 4' high, delivering
about 50KW or so.  Being synchronous (3 phase), it would ride over dips in
the power line and totally isolated the computer from nearby source of
electrical noise, which included

	- heavy arc-welding equipment,

	- a magnetic-squeeze former (a device for squeezing metal tubes,
	  bands, or bearings onto shafts using giant magnetic pulses produced
	  by discharging a large capacitor bank into coils of copper busbar),

	- a test stand for locomotive transmissions driven by a 1000HP
	  electric motor and loaded by a water-cooled Prony brake which 
	  cycled through start-forward-stop-reverse cycles at about one per 
	  minute.

We had NO power problems at that site.

					John Nagle