Thoughts, tips, suggestions on what UPS to use?

  • Thread starter Thread starter Doc
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Doc

I've got two computers - a PIV and a PIII that share a monitor. I use
them primarily for doing audio/video.

I thought I'd look into a UPS. What I'm looking for is mainly
something to guard against momentary power outs that might happen in
the middle of tweaking a file or the like. When I hear the lightning
coming near, I shut down and unplug everything. But around here, it
seems like the power can flick off at any time.

How much UPS would I need to protect and keep both computers going in
the event of a short brown out or power loss or keep them running at
least long enough to shut things down if it looks like the power is
going to be off for a while.

I've seen where there are issues with the type of power that comes out
of some UPS units. Are any of the units at Best Buy/Circuit City -
such as the APC brand - any good? What are important features to look
for? These various units have charts indicating how long they should
power a computer, but I don't know how realistic they are.

On the other end, how much unit would I need to keep a computer going
for say an hour if I were doing some rendering of a DVD and didn't
want to start over. I usually turn off the monitor when rendering
video, it's my understanding the monitor is a big power hog.


Thanks for all input.
 
Doc said:
I've got two computers - a PIV and a PIII that share a monitor.
Click to expand...

I'm going to estimate the PIII at 200 Watts, and PIV at 230 Watts. These are
likely close to the maximums. Do you have a CRT monitor, or an LCD? CRTs
typically pull up to 75 Watts, LCDs about 20. Based on this I would say you
need one that can sustain AT LEAST 450 Watts (generally 750VA in a UPS). If
you do this in two seperate UPS units, get two identical ones, put the PIII
and monitor on one, the P4 on the other. Also please note that I have not
included backup power for any peripherals.
How much UPS would I need to protect and keep both computers going in
the event of a short brown out or power loss or keep them running at
least long enough to shut things down if it looks like the power is
going to be off for a while.

I've seen where there are issues with the type of power that comes out
of some UPS units. Are any of the units at Best Buy/Circuit City -
such as the APC brand - any good?
Click to expand...

APC is widely well regarded, but some of their lower end products may be
questionable, but APC products are widely used throughout the computer
industry.
What are important features to look
for? These various units have charts indicating how long they should
power a computer, but I don't know how realistic they are.
Click to expand...

Generally they aren't too far off, but the battery will age and diminish in
capacity so make sure you have some extra capacity.
On the other end, how much unit would I need to keep a computer going
for say an hour if I were doing some rendering of a DVD and didn't
want to start over. I usually turn off the monitor when rendering
video, it's my understanding the monitor is a big power hog.
Click to expand...

That depends largely on the computer. P4 are notorious for their massive
power consumption with some systems consuming upwards of 600 Watts at peak
(you almost certainly don't have this). With a competent, but fairly minimal
configuration a P4 should be consuming only 180-190 Watts at peak
consumption, so assuming this is correct, and assuming you go with an APC
Back-UPS RS you'll want at least 1500VA, at that price point it will almost
be cheaper to upgrade to a more recent system which will allow you to have a
smaller UPS. Even moving to a generally inexpensive Core 2 Duo you'll likely
see at least 50 watts in savings and the same render speed, this will let
you move down to 1200VA.

Basically, my point being that a full hour is difficult to achieve with
consumer equipment, if you go to professional equipment prepare to pay
professional prices.
Joe
 
Basically, my point being that a full hour is difficult to achieve with
consumer equipment, if you go to professional equipment prepare to pay
professional prices.
Joe
Click to expand...

I agree with all of Joe's point. In addition, factor in that the
batteries need to be replaced; APC usually recommend it after 4 years,
IIRC. The replacement battery is likely to cost 60 - 75% of that of
the UPS itself. Of course you can just let them grow old, and test
them from time to time to see whether they still have enough capacity,
but they do tend to become unreliable, and will eventually be a
greater liability than the risk of a power cut - exactly what they're
supposed to be protecting you from.

If you want to be able to work for an hour without power, look at
buying a laptop. Hopefully there's one out there that you can fit a
second battery pack to, without having to remove the CD/DVD drive to
do so. It's probably going to be cheaper than the UPS you'll need to
achieve the same with your desktop PCs.

-Nick
 
I've used APC for years, and had no complaints (other than the high cost of
a replacement battery).

I know the unit's working correctly, because I sometimes hear it kick in for
a fraction of a second ("bwang!"). Over the past few months I've had at
least a dozen power glitches, and the APC has never failed to keep things
going.

On occasions when we lost power completely (eg, during wind storms), I had
plenty of time to shut down the computer. APC's estimates of running time
seem to be conservative. However, running two computers for an hour will
probably require more capacity than you're willing to pay money for.
Ignoring the loss of time, an outage when you're rendering a DVD would lose
you only a single blank disk, which costs a lot less than the added cost of
a high-capacity UPS.

By the way, these devices are not UPSs (uninterruptible power supplies), but
SPSs (standby power supplies). The distinction is that, with the former the
inverter is always powering the load, while in the latter, the inverter is
switched on only when power is lost.
 
but they do tend to become unreliable, and will eventually be a
greater liability than the risk of a power cut - exactly what they're
supposed to be protecting you from.
Click to expand...


A greater liability in what way? Are you referring to something
besides it leaving you vulnerable to a power outage? Will the UPS
itself cause problems?
 
A greater liability in what way? Are you referring to something
besides it leaving you vulnerable to a power outage? Will the UPS
itself cause problems?
Click to expand...

Yes. My experience of the cheaper APC units and similar from other
manufacturers is that when they fail they quite often do so in a way
that disrupts the equipment they're supposed to be protecting. I
remember looking at a APC SmartUPS 2200 last year, which had starting
failing its periodic self-tests so badly that it was causing the
attached servers to reboot every time it tested itself.

That isn't a criticism of APC, just that people tend to put these
things in and then forget about them until they start causing trouble.

-Nick
 
Doc said:
How much UPS would I need to protect and keep both computers going in
the event of a short brown out or power loss or keep them running at
least long enough to shut things down if it looks like the power is
going to be off for a while.
Click to expand...

Take the nameplate ratings off of everything you want to plug into the UPS.
That's both computers, the monitors, whatever external disk drives you
might have, etc. Tote the power values all up. If there is no power listed,
just a current, multiply the current by 120 to get approximate power in VA.
I've seen where there are issues with the type of power that comes out
of some UPS units. Are any of the units at Best Buy/Circuit City -
such as the APC brand - any good? What are important features to look
for? These various units have charts indicating how long they should
power a computer, but I don't know how realistic they are.
Click to expand...

All of the cheap standby units you describe produce lousy waveforms, but
you don't care about that since they're only running on inverter when the
power goes out. You'll find you will have audio issues when the UPS kicks
in, but hopefully you won't be tracking with the UPS kicking in anyway.

The UPS units will have a watt-hour rating. Divide it by your load in watts
and you'll know how long it will run. Most units can take external battery
packs as well for extended running times.
On the other end, how much unit would I need to keep a computer going
for say an hour if I were doing some rendering of a DVD and didn't
want to start over. I usually turn off the monitor when rendering
video, it's my understanding the monitor is a big power hog.
Click to expand...

It is, but the nameplate on the back will tell you how much.
--scott
 
Doc said:
I've got two computers - a PIV and a PIII that share a monitor. I use
them primarily for doing audio/video.

I thought I'd look into a UPS. What I'm looking for is mainly
something to guard against momentary power outs that might happen in
the middle of tweaking a file or the like. When I hear the lightning
coming near, I shut down and unplug everything. But around here, it
seems like the power can flick off at any time.

How much UPS would I need to protect and keep both computers going in
the event of a short brown out or power loss or keep them running at
least long enough to shut things down if it looks like the power is
going to be off for a while.

I've seen where there are issues with the type of power that comes out
of some UPS units. Are any of the units at Best Buy/Circuit City -
such as the APC brand - any good?
Click to expand...

Doc, they all actually work. None of them are junk. I prefer oversize units,
with replaceable gel cells. The Cyber power brand offers rack mount units
with all metal cabinetry and a fan that can be mounted vertically, on a
stand. The fan runs only when the inverter is active. The design of these
units keeps the gel cells cool, which is important to long life. I have had
two 1500AVR units:
http://www.cyberpowersystems.com/products/all/ups/browse-by-category/avr-series/CPS1500AVR.html
in operation for about five years. Occasionally, when I'm in the room, the
units kick in for a fraction of a second, impressing me with the fact that
they have saved the computers from a crash.

The "AVR" in the model number refers to "automatic voltage regulation", a
tapped transformer that compensates for sags and brownouts.

Until recently, all computer based units produced a modified square wave
output, also euphemistically referred to as a "modified sine wave." This is
perfectly fine for computers, but will likely inject some noise into audio
equipment. But practically speaking, UPSes do not have much runtime with all
but the most power sparing systems, such as laptops. Most UPSes come with
companion software that provide for automatic shutdown, or after an interval
you specify, or upon battery exhaustion.

UPSes do not provide more lightning protection than the typical surge strip,
which isn't much. You should probably also get a high quality surge
protector.

Bob Morein
Dresher, PA
(215) 646-4894
 
I've got two computers - a PIV and a PIII that share a monitor. I use
them primarily for doing audio/video.

I thought I'd look into a UPS. What I'm looking for is mainly
something to guard against momentary power outs that might happen in
the middle of tweaking a file or the like. When I hear the lightning
coming near, I shut down and unplug everything. But around here, it
seems like the power can flick off at any time.

How much UPS would I need to protect and keep both computers going in
the event of a short brown out or power loss or keep them running at
least long enough to shut things down if it looks like the power is
going to be off for a while.

I've seen where there are issues with the type of power that comes out
of some UPS units. Are any of the units at Best Buy/Circuit City -
such as the APC brand - any good? What are important features to look
for? These various units have charts indicating how long they should
power a computer, but I don't know how realistic they are.

On the other end, how much unit would I need to keep a computer going
for say an hour if I were doing some rendering of a DVD and didn't
want to start over. I usually turn off the monitor when rendering
video, it's my understanding the monitor is a big power hog.

Thanks for all input.
Click to expand...

For $20~$30 you can measure your actual power usage:

http://www.supermediastore.com/kilwateldet1.html

This is a handy gadget to have around. It is surprisingly accurate
too. Don't use it on the output of a stepped sine approximation type
UPS (the cheapies) as the waveform will burn up the P4400. It's ok to
use on a true (or nearly true) sine output UPS such as:

http://www.thenerds.net/APC_APC_SmartUPS_1500VA.SUA1500.html

Those are what I use. I have several for the studio. Computers have
one each and the critical audio components (minus amps and powered
monitors) on one. Interconnection between computers and audio via
lightpipe and jensen transformers to avoid power problems and
grounding issues with multiple UPS.

LCD monitors can pay for themselves if you are moving from a large
CRT, some of which consume upwards of 200W. We had four on all the
time. Replacing with four LCD monitors reduced power consumption by a
factor of 10. It was noticeable in the power bill.

bobs

Bob Smith
BS Studios
we organize chaos
http://www.bsstudios.com
 
For $20~$30 you can measure your actual power usage:
Click to expand...

Most UPSs are rated by VA or KVA rather than watts. You can probably
get a better assessment of the requirements by measuring the current
with a clamp-on ammeter. I picked up a Wavetek AD15 for $10 at a
hamfest. The seller had a big carton of them. I'll bet there must be
somebody selling them on eBay from the same stash.
 
Most UPSes come with companion software that provide
for automatic shutdown, or after an interval you specify,
or upon battery exhaustion.
Click to expand...

Many versions of Windows will recognize a UPS when its USB cable is
attached. However, I've had problems with the OS going into Standby when
there's a power glitch (not an extended outage), and had to turn off all the
automatic standby and hibernate modes.
 
Mike Rivers said:
Most UPSs are rated by VA or KVA rather than watts. You can probably
get a better assessment of the requirements by measuring the current
with a clamp-on ammeter. I picked up a Wavetek AD15 for $10 at a
hamfest. The seller had a big carton of them. I'll bet there must be
somebody selling them on eBay from the same stash.
Click to expand...

To accurately measure the power draw of computer power
supplies (for which the current waveform is *very*
nonsinusoidal), you need a waveform integrating watt meter.
Despite its low price, the Kill-a-Watt meter recommended
by a another poster in this thread is such a meter.

-- Bob Day
http://bobday.vze.com
 
William Sommerwerck said:
Many versions of Windows will recognize a UPS when its USB cable is
attached. However, I've had problems with the OS going into Standby when
there's a power glitch (not an extended outage), and had to turn off all
the
automatic standby and hibernate modes.
Click to expand...
This is why the companion software of the UPS is better. It's more
sophisticated than the built-in Windows management.

Bob Morein
Dresher, PA
(215) 646-4894
 
Most UPSs are rated by VA or KVA rather than watts. You can probably
get a better assessment of the requirements by measuring the current
with a clamp-on ammeter. I picked up a Wavetek AD15 for $10 at a
hamfest. The seller had a big carton of them. I'll bet there must be
somebody selling them on eBay from the same stash.
Click to expand...

Mike,

The Kill-A-Watt will measure VA or Watts and also power factor in
addition to volts and amps. IIRC the circuit is from an Analog Devices
application note. Some fellow put up his comparison of this device
against a current probe, Tek scope and HP meter. It was pretty close
for all practical purposes. It self powers from the source which is
why it doesn't like stepped approximations of sine for volts which can
burn up the internal supply.

bobs

Bob Smith
BS Studios
we organize chaos
http://www.bsstudios.com
 
Many versions of Windows will recognize a UPS when its USB
This is why the companion software of the UPS is better. It's more
sophisticated than the built-in Windows management.
Click to expand...

The companion software probably wouldn't be needed if the Windows shutdown
management weren't buggy. I have "too much" software on the machine as it
is, and decided not to install the APC drivers.

APC worked with me on this problem, and I finally discovered that setting
power scheme "System standby" setting to Never for both AC and battery
operation resolved the issue. APC made no strong claims as the superiority
of their software.
 
The Kill-A-Watt will measure VA or Watts and also power factor in
addition to volts and amps.
Click to expand...

Hard to tell that from the description. I tried to find a web site for
the original manufacturer to read more but wasn't successful. For
$20. it sounds like a handy gadget to have around.

Mostly I wanted to make it understood that watts are not necessarily
numerical to volt-amperes. Most computer equipment is specified in
watts, most UPSs are rated in V-A.
 
I agree with all of Joe's point. In addition, factor in that the
batteries need to be replaced; APC usually recommend it after 4 years,
IIRC. The replacement battery is likely to cost 60 - 75% of that of
the UPS itself. Of course you can just let them grow old, and test
them from time to time to see whether they still have enough capacity,
but they do tend to become unreliable, and will eventually be a
greater liability than the risk of a power cut - exactly what they're
supposed to be protecting you from.

If you want to be able to work for an hour without power, look at
buying a laptop. Hopefully there's one out there that you can fit a
second battery pack to, without having to remove the CD/DVD drive to
do so. It's probably going to be cheaper than the UPS you'll need to
achieve the same with your desktop PCs.

-Nick
Click to expand...

While a battery might be routinely replaced at the 4 year
mark to retain runtime, if it had rarely been used, the
replacement interval will be shorter if the battery is
frequently used or ran down further (system is kept running
as long as possible, as with the formerly expressed desire
to keep running the system for an hour while under high load
(compressing video).
 
I agree with all of Joe's point. In addition, factor in that the
batteries need to be replaced; APC usually recommend it after 4 years,
IIRC. The replacement battery is likely to cost 60 - 75% of that of
the UPS itself. Of course you can just let them grow old, and test
them from time to time to see whether they still have enough capacity,
but they do tend to become unreliable, and will eventually be a
greater liability than the risk of a power cut - exactly what they're
supposed to be protecting you from.

If you want to be able to work for an hour without power, look at
buying a laptop. Hopefully there's one out there that you can fit a
second battery pack to, without having to remove the CD/DVD drive to
do so. It's probably going to be cheaper than the UPS you'll need to
achieve the same with your desktop PCs.

-Nick
Click to expand...

Also with many UPS you don't have to buy the battery from
the UPS manufacturer and can save quite a bit of money
there. They often use common sizes of SLA batteries which
don't even have the same quality issues as you'd have to
beware of with replacing Li-Ion packs for notebooks/etc. -
since SLA is generally a simple and mature tech and the
charging control portion is all in the UPS so that remains
constant.

The notebook idea is a good one, it will be easier to keep
one running for an hour and if these outtages are that
common, it is nice to have a notebook. However it is also
nice to suppliment that with an UPS for a modem / wifi
router so the laptop retains internet access. On the other
hand, if these video compression jobs are frequent and
considering the need to start such jobs on the laptop for
them to be running still when power goes out, this
continuous high load on a laptop can tend to wear it out
faster.
 
Mike Rivers said:
Hard to tell that from the description. I tried to find a web site for
the original manufacturer to read more but wasn't successful. For
$20. it sounds like a handy gadget to have around.

Mostly I wanted to make it understood that watts are not necessarily
numerical to volt-amperes. Most computer equipment is specified in
watts, most UPSs are rated in V-A.
Click to expand...

Mike-

The Kill-A-Watt is made (or imported?) by P3 International,
http://www.p3international.com/products/special/P4400/P4400-HG.html
and they have a toll free phone number for information. I ordered mine
from a company suggested by P3. It does not have "commercial grade"
construction, but the price isn't commercial grade either.

I purchased mine for use with emergency power generators. (The 60 Hz
frequency read-out is handy for checking generator engine speed.) I
also have a digital voltmeter rigged-up with a loop of wire for use with
a Fluke clamp-on current probe.

The Kill-A-Watt claims to be true-RMS, while my other meters are
average-reading calibrated for sine wave. For commercial power, the
Kill-A-Watt readings are very close to the other meters. However, for a
generator with an imperfect sine wave, they often disagree. I expect
the Kill-A-Watt would be the best for odd waveforms such as the computer
power supply current.

Fred
 
Hard to tell that from the description. I tried to find a web site for
the original manufacturer to read more but wasn't successful. For
$20. it sounds like a handy gadget to have around.

Mostly I wanted to make it understood that watts are not necessarily
numerical to volt-amperes. Most computer equipment is specified in
watts, most UPSs are rated in V-A.
Click to expand...

That is a good point and why the Kill-A-Watt is so useful because you
can read both VA and Watts and work with whichever units are most
convienient.

bobs

Bob Smith
BS Studios
we organize chaos
http://www.bsstudios.com
 
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