In article , mm wrote:
On Mon, 26 Feb 2007 17:45:22 GMT, (Malcolm Hoar)
wrote:



If they are 12 volts, you could take your car battery out and
temporarily hook it up to the UPS to see if it would work. Or string
together a bunch of flashlight batteries, preferably rechargeable.

Please do NOT try this unless you really know what you're
doing. And if you really knew what you were doing, you'd
know enough not to do this.

Which part, the car battery or the 8 flashlight batteries?

I wouldn't do either (and I'm an EE by training).

But especially don't mess with the car battery.

And why shouldn't you do it?

1. A car battery contains a LOT of stored energy.
Those really thick cables attached to your car
battery are thick for a reason.

2. It's easy to release that energy very rapidly (e.g.
with a short).

3. The probabily of an accidental short is HUGELY
increased with quick and dirty temporary wiring.

4. In the event of a short, the resulting explosion
can cause concentrated acid to be sprayed all over
the area as well as globs of molten copper and more.
Trust me, you don't want to be near by.

It's about as dangerous as fooling around with a
chain saw except that the dangers are a lot less
obvious to a casual observer.

What would you have to know to know what you're doing?

Don't connect large capacity batteries (esp. lead acid)
using anything except properly rated cables and connectors/
terminations.

In the case of a UPS, the said applicance is simultaneously
connected to the utility power creating even more scope
for accidents. A broken UPS is by definition umm, broken,
increasing the risks still further since it may do things
that are unpredicable and out-of-spec.

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
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