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From: johne@hp-vcd.HP.COM (John Eaton)
Newsgroups: sci.electronics
Subject: Re: Bullshit, or NOT? AC line problems.
Message-ID: <2470012@hp-vcd.HP.COM>
Date: 7 Feb 91 17:38:19 GMT
References: <1991Feb5.005045.388@miavx2.ham.muohio.edu>
Organization: Hewlett Packard, Vancouver, WA
Lines: 23

<<<
< high-resistance neutral, but frankly, with today's superior power
< supply designs, it's rare for that to be a real problem.
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Todays switching supplies are superior in size,cost and efficiency
but are lousy as loads. They act as negative resistance by drawing
more current as the voltage decreases and tend to only draw current
during the peak times of the AC cycle. This leads to problems with
harmonics on the AC line. I have heard of one case where a large
number of PCs on a line caused excessive current on the ground
line and started a fire. Some safety agencies are looking into
regulating the harmonics that a supply can put onto the AC line.


<I think your CE is totally stumped and looking for excuses.
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Could be. I would check to see that all grounds are solid and
non current carrying. Move PC's around to see if the problem
follows a machine or an outlet.


John Eaton
!hp-vcd!johne