[unix-pc.general] Leave Diagnostic Disk In?

gmark@ihlpf.ATT.COM (Stewart) (05/20/88)

A while ago, someone stated on the net that they made a practice of
leaving the diagnostic disk in, so that, in the event of a power
problem, it would start to boot and sit there.  This would prevent
the repeated cycling that could damage the HD.  Has anyone been
doing this, and has ANYONE had any problems with it?  Might it be a
better idea to switch the power through a latched relay, so that
a power outage would disconnect power from the machine permanently
until someone manually reset the latch?  What I'D like to do is
to set the darn thing to switch off permanently in the event of an
overheating until I reset the thing -- like a thermostatic circuit
breaker.  Comments?????????????

				- Mark

				G. Mark Stewart
				ATT_BTL, Naperville, Ill. ix1g266
				ixlpq!gms (312)979-0914
				(please include phone in response)

mother@sunspot.UUCP (Leonard Sitongia) (05/20/88)

In article <4813@ihlpf.ATT.COM> gmark@ihlpf.ATT.COM (Stewart) writes:
>... What I'D like to do is
>to set the darn thing to switch off permanently in the event of an
>overheating until I reset the thing -- like a thermostatic circuit
>breaker.  Comments?????????????
>
>				- Mark
>

I've installed a thermal fuse in-line on the 115v between the
fuse/switch element and the power supply board.  This was just a simple
fuse that opens up at a certain temperature and was crimped in (not
soldered).  Ive seen that other types of thermal fuses are available,
including resetable ones.  The simple fuse I installed cost about $5
from a electronics supply house.
-- 
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bob@rush.cts.com (Bob "Rush" Ames) (05/21/88)

In article <4813@ihlpf.ATT.COM>, gmark@ihlpf.ATT.COM (Stewart) writes:
> A while ago, someone stated on the net that they made a practice of
> leaving the diagnostic disk in, so that, in the event of a power
> problem, it would start to boot and sit there.  This would prevent
> the repeated cycling that could damage the HD.  Has anyone been
> doing this, and has ANYONE had any problems with it?  Might it be a
> better idea to switch the power through a latched relay, so that
> [...]

I think that the poor man's solution to this is this GREAT idea by
Mark.  I don't see any problems with leaving the diagnostic disk in.

I believe AT&T recommends that this machine be left on 24 Hours a day.
I do this, but in addition to this, I recommend performing a shutdown
and leave the machine at the 'Ready to press <RETURN> to re-boot'
prompt if you don't plan to use your machine for a couple of days.
With this new idea, you can have your cake and eat it too.  Just
shutdown, leave diagnostic disk (copy) in the drive, and leave the
power on.  With 3.5 or greater, the screen blanking will automatically
dim the console.

The latched relay is the better solution though.

BTW:  I've calculated that my machine costs about $15.00 per month
to keep on 24Hours a day.  This is based on San Diego Gas & Electric
company's third-highest-in-the-nation electric rates.  Your costs
will probably be lower.  So leave your computer on and make it last.

Does anyone disagree with AT&T's recommendation to keep the machine on?

Bob Ames

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