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Dave Ihnat wrote:
On Fri, Jan 02, 2009 at 06:55:00PM -0500, Robert L Cochran wrote:
That is what I want to see -- far lighter weight batteries ...  >
... Lithium polymers would be great for this sort of application. They
should be linux-friendly, ...

First, appliances should be OS-independent; they should talk a "common
language", that doesn't care if it's on Windows, Linux, Unix, etc.

Secondly--as you'll continue to see me state in this post--the problem
is that everyone wants "cheapest possible".  That means they go for
things like lead acid--cheap, mature--and LCD on any drivers or
associated software.

As a result of the various posts in this thread, ...

Essentially, batteries are batteries.  The vendors aren't going to go to
the immediate cost of custom "smart" batteris and support costs of a
specialized battery.

This still does not really meet my criterium of being very quick to
replace and instantly usable.

To meet that criterion, you essentially need to find a local battery
supplier who has either original vendor replacement batteries, or
acceptable aftermarket units designed for your UPS.  Given the economy
and the decline of bricks'n'sticks stores, good luck.

I wish there were a way to independently, accurately and easily test the
UPS itself ...
Having the ability to test the units, regardless of devices connected to
the UPS, is critical.

Again--the end users are demanding cheap.  They get cheap.

The APC units are still way too heavy and bulky. They are poorly
designed, being little more than batteries stuffed into a box that are
connected to circuit boards and 120v outlets.

Cheap.  See above.

The most depressing part of all of this is that companies producing
professional-quality units aren't rewarded, so they either die or turn
out low-end junk...as we're seeing.

You get what you pay for. If I had a really critical application I would look at Exide "double conversion" units, which handle a vast range of power problems which cheap units do not. I used some in NYC at the last 'Linux World' in the Javits Center where the house power had phase shifts (PF ranged from .85 to .86 or so with 20-40ns 1100v pulses) and the output side was just flat out clean. And with DC in a brownout you use only whatever battery it takes to make up the difference between available and needed power.

Not cheap, but $600 for a 650 is not break the bank, either, and they make big units to give your generator time to come up to speed. Disclamer: only a very satisfied customer.

Bill Davidsen <davidsen tmr com>
  "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

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