[ale] OT: question about replacing batteries in a APC UPS
Matt Macumber
matt.macumber at gmail.com
Thu Dec 22 09:08:22 EST 2005
Canada runs 120V 60Hz, plug types A and B just like the U.S.
Matthew.
On 12/22/05, Courtney Thomas <cc.thomas at earthlink.net> wrote:
> Mike,
>
> Thank you for the thorough and thoughtful reply.
>
> Unrelated questions to which I'd appreciate a response is:
>
> can U.S. equipment made for 120v be used in Canada, which I understand
> has 220v as standard home installation ?
>
> if no, what, if anything, can be done to render such equipment usable
> in Canada ?
>
> Again, gratefully,
>
> Courtney
>
>
>
>
> Mike Harrison wrote:
> > Courtney asked:
> >
> >>What and how do the testers reveal ?
> >
> >
> > Disclaimer: This is potentially dangerous, don't touch anything metal,
> > don't wear shoes with metal tacks in the heels.. don't.. (it's a long list)
> >
> >
> > Good question. Set to AC Volts, (Alternating Current) you can test an
> > outlet as follows:
> >
> > The outlet should have 3 plugs.. 2 slots, one larger than the other
> > and a round hole:
> >
> > [ |
> > o
> > The larger slot on the left is 'neutral' the smaller one on the right
> > is 'line' or 'hot' and the small circle is 'ground'.
> >
> > In a perfect world. 'hot' has a sine wave of approximately 117 volts
> > calculated as a 'root mean square' average of alternating electrical
> > potential. You want to make sure it's there, and that 'neutral' is
> > at 0 volts, as is ground.
> >
> > So with your el-cheapo voltmeter, stick the probe tip black lead in
> > the 'neutral' and the red lead into 'hot'. You should get 110 to 120 volts AC.
> >
> > Then move the red lead into 'ground'. You should get 0 volts. Maybe 0.5volts.
> > but it should be 0. Ground and neutral (in most systems) tie into the
> > same place back at the breaker panel.. they should have the same
> > potential.
> >
> > Then move the black lead to 'hot'. You should get 117 volts. If not,
> > your ground is open, not grounded. Very common problem in houses.
> > The purpose of the ground wire is safety. The metal chassis of a
> > device uses the ground wire as a redundant path back to the breaker
> > box. If there is 'leakage' via EMF from high voltage electronics
> > or transformers or.. (lots of things), it should drain down the
> > ground wire. If it is 'open', a shock potential from the device may
> > exist. Grounds are also a catastrophic failure protection means.
> > If a power supply 'melts down' and shorts to ground, the current
> > should travel back to the break panel at close to 0 volts, and if the
> > current level is high enough, allow the breaker to trip.
> >
> > Last test: paranoid mode. If you have something that is grounded
> > handy, like a metal copper pipe that goes into the earth, large metal
> > structural supports.. etc.. - Measure between it and the Ground and
> > Neutral and make sure it's 0 volts or really really close to it. (.5volt?)
> > and measure between the natural earth ground and 'hot' you should get
> > 110-120 volts.
> >
> > So.. If all is good, you have a properly wired electrical outlet, there is
> > one good 'idiot check' you can make on your UPS:
> >
> > Set your meter to Ohms. A measure of electrical resistance.
> >
> > With your UPS unplugged, put the black lead on the round pin.
> > then put the red volt meter lead on any metal on the case.
> > It should be under 1 ohm. Now move the red lead to the round
> > plug hole on the outlets. Same thing. 1ohm or less.
> >
> > On some UPS's you MAY be able to do this with 'hot' and 'neutral' on
> > the outlet to the cord plug end for hot and neutral, depends
> > if it's using a relay for power pass through and what it's position
> > is when 'off'.
> >
> > Plug your UPS in and turn it on. Repeat the first set of steps for the
> > outlets on the UPS.
> >
> > Last test. turn off the power to the UPS, but keep it plugged in (so
> > ground is still attached) so that the UPS is running on batteries.
> > It may work better if something is plugged in and running off the UPS
> > as many of them require a load. Then do the tests again. You will get
> > something approximating 110-140 volts from neutral to line on the UPS, it
> > depends on the quality of the site wave your UPS generates. It may read
> > high if there is no load or a very small one, and/or it produces a squarer
> > waveform than normal line power.
> >
> > ----------------
> >
> > Honest disclaimer: I've done these tests and more.. but I usually
> > just plug them in and see if they work. :) - I did check out the wiring in my house
> > when I bought it for proper polarity of the pins, and good grounds..
> > and again when I put in the generator and UPS's.. but I'm insane.
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > Ale mailing list
> > Ale at ale.org
> > http://www.ale.org/mailman/listinfo/ale
> >
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://www.ale.org/mailman/listinfo/ale
>
More information about the Ale
mailing list