dpb wrote:
....
protection from automagic restart after a power glitch is a _BIG_ safety
factor that goes away w/ a mechanical switch.

I've never seen all that much value in such protection. I think of it
this way: what's the probability that I'll be using a machine at the
time of a power outage? And what's the probability that I'll forget the
turn the switch off before I leave the machine? And what's the
probability that there will be any dire consequence to it coming back on
without me there? Multiple those probabilities and overall risk is so
low that I don't give it a second thought.

Bob

"Bob Engelhardt" wrote in message
...
dpb wrote:
...
protection from automagic restart after a power glitch is a _BIG_ safety
factor that goes away w/ a mechanical switch.

I've never seen all that much value in such protection. I think of it
this way: what's the probability that I'll be using a machine at the time
of a power outage? And what's the probability that I'll forget the turn
the switch off before I leave the machine? And what's the probability
that there will be any dire consequence to it coming back on without me
there? Multiple those probabilities and overall risk is so low that I
don't give it a second thought.

I think part of the safety issue is "unclean" re-introduction of power from
outages, brownouts, you know, that bzzzzzt-bzzzzt-bzzzzzt type of stuff,
mebbe crazy backfeeds from people with generators, just multiple on-offs,
on-offs, etc. A main contactor for the whole house might not be a bad
idea....

If I come down to a dark shop, I know the main contactor dropped out, from
some power glitch.
--
EA



Bob

On 8/15/2012 11:23 AM, Bob Engelhardt wrote:
dpb wrote:
...
protection from automagic restart after a power glitch is a _BIG_
safety factor that goes away w/ a mechanical switch.

....

without me there? Multiple those probabilities and overall risk is so
low that I don't give it a second thought.

It's not without you that matters quite so much--it's while around that
is the gotcha' time...

And until it happens...then you'll think about it a lot, garon-teed.

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