🚀 go-pugleaf

isbell@cats.ucsc.edu (Art Isbell) writes:
[need UPS]
>What rated capacity is recommended for a NeXT Cube with an external floppy and
>CD-ROM drive and a modem (I think I'd need to keep all of these running during
>a power failure).  NeXTanswers reports that an idling Cube draws less than 150
>watts of power (maybe around 115 W., but I can't recall for sure).  My
>peripherals are low-power devices, so I would think that my VA load would be
>no more than 300 (I think volt-amps = 1.4 * watts).  I don't want to buy a
>bigger UPS than I really need, although I guess I could run longer on a larger
>UPS.

What do you need the UPS for? Do you just want to do a safe shutdown
(keep the system up for 5 or 10 minutes after power failure and send
SIGPWR) or do you want to keep the system up and running for the full
time (1 hour? 2 hours? 24 hours?)???

Bye, Olli

-- 
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In <1croojINN3c2@darkstar.UCSC.EDU> isbell@cats.ucsc.edu (Art Isbell) writes:

>What rated capacity is recommended for a NeXT Cube with an external floppy and
>CD-ROM drive and a modem (I think I'd need to keep all of these running during
>a power failure).  NeXTanswers reports that an idling Cube draws less than 150
>watts of power (maybe around 115 W., but I can't recall for sure).  My
>peripherals are low-power devices, so I would think that my VA load would be no
>more than 300 (I think volt-amps = 1.4 * watts).  I don't want to buy a bigger
>UPS than I really need, although I guess I could run longer on a larger UPS.

Since I have a very similar setup and just got a UPS, I think I'll
comment.  Plus add some extra for other folks.

I have a NeXT Cube, external hard drive, modem, and soon will have a
CD-ROM drive.  I currently own a 660VA BEST Fortress UPS.  It runs
currently at about 40% load and will probably hit 45-50% with the
CD-ROM.  And I get about 25-30 minutes of backup time.  Remember to
consider if you have an OD drive, that'll chew up some more power.

Anyways, the BEST catalog has this to say about determining the
Volt/Amps (VA) rating you should get and this should apply to any UPS.

1) List **ALL** equipment that will be protected by the UPS.

2) Check the voltage and amps, then multiply them together to get your
VA rating for that device.  If it gives just a figure for Watts,
multiply that by 1.4.

3) Add up all VA requirements.

4) Give room for growth.  Mutiply by 1.25 to get a 25% growth factor.
This will be the total value for a VA requirement.

Now when I talked to BEST they told me that even though they tell you
this is how you should calculate it, more often than not, manufactures
specifications for power consumption is for the absolute greatest
possibly that you can consume.  For a NeXT Cube that would be 300W at
5A. A fairly large load.  You can therefore lower your VA requirement
some.  But you definitely want some room to spare, powerwise, for your
UPS.  For me, the next model down would have been a 460VA unit which
would have sufficed but would have been operating at about 85-90%
capacity.  Not good.

>I'd also like to get a UPS with maintainable batteries (apparently the sealed
>maintenance-free batteries supplied with many UPS's eventually fail because
>they dry out, so the ability to add water periodically could extend battery
>life by a factor of 2 - 4).

BEST uses sealed ones.  But they also offer some kind of warranty that
covers their batteries.

>Any guidance, words of wisdom, suggestions, etc. would be appreciated.  I will
>summarize to the net.

I've been extremely happy with my BEST Fortress.  It is a sleek
efficient model.  It has a nice readout display that you can change
various paramaters of it's operation, it offers a very nice advanced
communications off a RS-232 port, which you can buy software for to
shutdown your computer.  You can check voltage in, out, runtime,
%loads, and more.  They have been given great ratings for a number of
people,  Their staff are very easy to deal with and very glad to help
you out.  Even though they sell their own software for communicating
with their UPS's, they will gladly give you documentation on exactly
what you can do across the communication port so you can work with
them.

I would highly recommend BEST products to anyone looking for a UPS.

-doug

I second the recommendation for BEST.  We are using one of their
larger UPS's (the Micro-Ferrups line) to protect a small machine room.
It has worked flawlessly since the day we installed it.


barry
-- 

We have a 1200VX made by APC.  It is massive overkill.  It can run the
NeXTstation 2 modems and some other equipment for well over an hour.


You should know that you can buy a small APC for around $100 now.   One
feature that makes them very attractive is that they can be configured
to run an RS232 connection into your machine and shut it down (ie, call
shutdown -p) before the UPS runs out of juice.  I think this is a 
wonderful feature.

	---Russ