[comp.sys.att] power-fail monitor ??

thad@cup.portal.com (Thad P Floryan) (10/09/90)

rhaar@rcsrlh.Berkeley.EDU (Bob Haar CS50) in <34900@rphroy.UUCP> writes about
using a UPS with his UNIXPC.

Due to recent workload I've only had a few minutes each day to read Usenet,
but always at least look at the UNIXPC newsgroups.  One item in Bob's posting:

``	[...]
	ps:(2) I made a test to see how long the UPS would last. After
	charging the battery overnight, I unplug the UPS from the wall socket.
	[...]
''

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For YOUR safety, do not EVER unplug devices such as a UPS or SPS from a wall
socket to test them: you lose the protective grounding of the 3rd prong.

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Instead, use a switchable power strip into which the UPS (or SPS) can be
plugged, then flip the strip's switch to OFF for testing the UPS (assuming
your UPS/SPS doesn't have a self-test switch).

Alternately, again leave the UPS/SPS plugged into the wall socket in areas
where extension cords and/or power strips aren't permitted (such as Palo Alto,
CA, as one for-instance), then manually trip the circuit breaker servicing
that wall outlet.

Thad Floryan [ thad@cup.portal.com (OR) ..!sun!portal!cup.portal.com!thad ]

rhh@alice.att.com (r hardin) (10/10/90)

In article <34655@cup.portal.com>, thad@cup.portal.com (Thad P Floryan) writes:

> For YOUR safety, do not EVER unplug devices such as a UPS or SPS from a wall
> socket to test them: you lose the protective grounding of the 3rd prong.

I don't see why, offhand. There's no return path through ground either.

My TrippLite bc450b comes with a booklet that says:

``To test unit and simulate a blackout, pull the battery backup unit's
plug from the live outlet. The GREEN line power light should go
off while the RED battery light should turn on along with the
autible alarm. The intermittent alarm can be silenced by pushing
the audible alarm switch on the front of the battery backup. When
AC power returns alarm will reset automatically.''

It does mention that you should NEVER (their caps) plug it into itself :-)
or it self-destructs.