[Tfug] FTGH: APC Back-UPS Pro 650

[johngalt1]

----- Original Message ----- 
From: "Sean Warburton" <>
To: "Tucson Free Unix Group" <tfug at tfug.org>
Sent: Friday, April 20, 2007 7:12 PM
Subject: Re: [Tfug] FTGH: APC Back-UPS Pro 650


> I'm sorry! I didn't know a series/parallel discussion
> would ensue...Here was
> how I found it: the positive went somewhere into the unit,
> and the negative
> went directly to the positive in the second battery. the
> negative from the
> second battery went somewhere...so whatever configuration
> that is...could I
> add more batteries (hooked up positive to negative, like
> the original two
> were) to get increased run time (I think Rich as hinting
> at this...)?

Yeah, you can daisy chain additional battery packs, but only
up to a point. Then after discharge, the batteries will
recharge so slowly that it becomes a problem.

Excluding the higher end systems, only APS XL version UPSes
are really designed to handle external batteries, so they
have higher current charging capacity. (from an article in
the APC knowledge base)

On APC Smart UPS 1400VA units,  I added some external
chassis (from eBay) that contain two more 24 V packs each.
It works pretty good. With one or two extra chassis, it
charges OK. But with more packs, it takes up to a day to
recover after a runtime calibration. I wonder how well these
UPSes handle that kind of duty cycle.