Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dpbst3
From: dpbst3@unix.cis.pitt.edu (David P Brennan)
Newsgroups: comp.sys.laptops
Subject: Re: Can Laptops be powered from Car Batteries?
Summary: voltage inverters not good
Message-ID: <130155@unix.cis.pitt.edu>
Date: 20 May 91 15:37:55 GMT
References: <18820001@hpspdra.spd.HP.COM> <18820003@hpspdra.spd.HP.COM>
Organization: University of Pittsburgh
Lines: 27

In article <18820003@hpspdra.spd.HP.COM> tomm@hpspdra.spd.HP.COM (Tom Menten) writes:
>   
>   Well, this weekend, I heard the "voltage inverter" (12DC to 110AC) 
>   described as a preferred solution, allowing all sorts of things to
>   be plugged in.  Then I spoke with a technical support person for one
>   of the mail order laptop companies who pointed out some problems:
>   apparently the inverters (at least some of them, presumably including
>   the less expensive variety most of us would consider purchasing) cause
>   a radio frequency "hash" that could cause problems for some plugged in
>   appliances, and also for nearby electronics (especially boat electronics!)
>   He was much more comfortable with generating systems than inverters.
>
I had posted the original description about the voltage inverter and after
checking into it a bit further I would caution against trying to use one
to power ANY computing equipment. The product listing in MCM Electronics'
catalog (Dayton,OH) includes a warning to not use a voltage inverter with
any microprocessor-based device, including computers. Apparently inverters
do not put out  a stable level of power. They are designed to provide site
power for drills, saws, pumps etc. Things that don't particularly care
what kind of power they get.
Trying to run a laptop in a boat seems to be a unique and difficult problem
to solve....I think it might be a good idea to just invest in 3-4 extra
battery packs and charge them before going out.

Dave Brennan
UPitt SLIS
dpbst3@unix.cis.pitt.edu