Nut upsuser - Jun 2005 - Off Topic: UPS units and heat generation

Hi all

A slightly off topic post, but one that I think someone out there in the 
NUT community could probably help me with.

Summer is coming, and my office at home is getting hot... helped in part 
by the APC 3KVA UPS I have sitting under my desk. It kicks out heat like 
a bar-heater, even when there is almost no load on it (idle load is one 
PC, one switch, one wireless AP, and thats it). It is very warm to the 
touch, and just gets worse when I turn on the rest of the kit (tape 
autoloader, TFTs, CRTs, two other PCs). With the UPS kicking out heat, 
and the outside temps going up and up, my AirCon unit was on pretty much 
all weekend to stop the kit (and myself) from melting.

Trying to get "idle heat generation" information about UPS units from 
any manufacturer is quite hard. Its not one of the items they have on 
their spec sheets or website, and my attempt at getting info from APC 
involved them being more interested in who I was, where I worked, where 
I got the UPS from, what its serial number was, etc than actually 
wanting to answer my question (I gave up eventually). Yes, I know the 
major reason for having a UPS is to protect the attached kit from power 
outages and spikes, but there are other things to consider beyond that.

Does anyone have any links, tips or helpful info in choosing UPS units 
that dont want to heat the room up? Would it be better to buy one big 
unit to cover my home office kit (like I have now), or a few smaller 
ones (one per PC, plus one for extra kit).

Sorry for the slightly off topic post, but my alternative would be to 
ask the slashdot crowd, and have to wade through numerous messages about 
"first post", GNAA, "In soviet russia, you heat the UPSs",
"In Korea,
only old people use UPSs", etc :)

Many thanks for your help in advance, it is greatly appreciated.

Steve

Hi Steve
> A slightly off topic post, but one that I think someone out there in the
> NUT community could probably help me with.
first, remember that not everybody has yet switched to these
new lists, so there won't be lots of answers for the moment...
> ...
> Trying to get "idle heat generation" information about UPS units
from
> any manufacturer is quite hard. Its not one of the items they have on
> their spec sheets or website, and my attempt at getting info from APC
> involved them being more interested in who I was, where I worked, where
> I got the UPS from, what its serial number was, etc than actually
> wanting to answer my question (I gave up eventually). Yes, I know the
> major reason for having a UPS is to protect the attached kit from power
> outages and spikes, but there are other things to consider beyond that.
You've got to correlate the QOS (Quality Of Service, ie the type
of UPS between offline, line interactive and online) with the actual
load on output. That will generate more or less heat.

The rule of thumb is: the best quality, the more heat generated...

Lastly, that's the first time I hear this question. Generally, people
look toward QOS and runtime, more than generated heat, but
that's because line-int. and online are in air cond. room...
> Does anyone have any links, tips or helpful info in choosing UPS units
> that dont want to heat the room up? Would it be better to buy one big
> unit to cover my home office kit (like I have now), or a few smaller
> ones (one per PC, plus one for extra kit).
sadly, no. I haven't any doc nor link on that point...

I'll just point, as always, MGE's UPS selector:
http://www.mgeups.com/selector/ups/

I can then put you in touch with some MGE representative to talk
about this point...

Arnaud Quette
---
Linux / Unix Expert - MGE UPS SYSTEMS - R&D Dpt
OpenSource Developer - http://arnaud.quette.free.fr/
Debian Developer - http://people.debian.org/~aquette/
... and much more ...