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" wrote in message
oups.com...
I've got two computers - a PIV and a PIII that share a monitor.

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?

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.

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.

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

On 15 Jul, 06:21, "Joseph Ashwood" wrote:

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

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

On Jul 15, 4:14 am, Nick Brown wrote:

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.


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?

On 15 Jul, 11:42, Doc wrote:
On Jul 15, 4:14 am, Nick Brown wrote:

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.

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?

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

On Sun, 15 Jul 2007 01:14:09 -0700, Nick Brown
wrote:

On 15 Jul, 06:21, "Joseph Ashwood" wrote:

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

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

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).

On Sun, 15 Jul 2007 01:14:09 -0700, Nick Brown
wrote:

On 15 Jul, 06:21, "Joseph Ashwood" wrote:

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

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

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.

Nick Brown wrote:
On 15 Jul, 06:21, "Joseph Ashwood" wrote:


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


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.

Generally, a UPS allowing real work during an outage is mostly
unrealistic, except for labtops, or with a serious price premium.

Main role of a UPS is to maintain power for the few minutes outages
usually lasts (location and provider quality/stability dependant, of
cause), and to automatically shutdown the gear to prevent damage.
Your computers are somewhat old and likely subject to near future
substitution, which you may want to take into consideration.

However, you're using the gear for audio/video, and I've seen comments
to noise generated by the USP onto the ac grid behind it.
Maybe using power conditioners on all gear is the solution.

I can't verify either, and need info on this myself. Comments needed..

--
Kind regards,
Mogens V.

On Tue, 17 Jul 2007 11:59:08 +0200, "Mogens V."
wrote:

Nick Brown wrote:
On 15 Jul, 06:21, "Joseph Ashwood" wrote:


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


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.

Generally, a UPS allowing real work during an outage is mostly
unrealistic, except for labtops, or with a serious price premium.

Main role of a UPS is to maintain power for the few minutes outages
usually lasts (location and provider quality/stability dependant, of
cause), and to automatically shutdown the gear to prevent damage.
Your computers are somewhat old and likely subject to near future
substitution, which you may want to take into consideration.

However, you're using the gear for audio/video, and I've seen comments
to noise generated by the USP onto the ac grid behind it.
Maybe using power conditioners on all gear is the solution.

I can't verify either, and need info on this myself. Comments needed..

My experience of UPS is mainly third world. There, its purpose is to
span the few minutes between the power going off and somebody firing
up the diesel genny.

d

--
Pearce Consulting
http://www.pearce.uk.com

On Tue, 17 Jul 2007 11:59:08 +0200, "Mogens V."
wrote:


However, you're using the gear for audio/video, and I've seen comments
to noise generated by the USP onto the ac grid behind it.
Maybe using power conditioners on all gear is the solution.

I can't verify either, and need info on this myself. Comments needed..


Any decent audio gear should be immune to noise on the AC
lines. It can't be built with the assumption the AC power
is a perfect/clean sine wave without an UPS present since
that would already be unrealistic. Even subcircuits within
the same gear will generate noise that must (/should/) be
rejected by the other subcircuits (one way or another).

If the gear can't handle that, IMO it should just be
replaced or the flaws fixed. At that point if it is felt
there is still room for improvement, rather than a general
power conditioner look into something specific, "Balanced
Power". http://www.equitech.com/faq/faq.html

kony wrote:

Any decent audio gear should be immune to noise on the AC
lines. It can't be built with the assumption the AC power
is a perfect/clean sine wave without an UPS present since
that would already be unrealistic. Even subcircuits within
the same gear will generate noise that must (/should/) be
rejected by the other subcircuits (one way or another).

Sadly, life isn't that way. And a lot of that audio gear is fine with
maybe 1% THD on the power line, but goes berserk with the poor waveform
that a typical UPS produces.

If the gear can't handle that, IMO it should just be
replaced or the flaws fixed. At that point if it is felt
there is still room for improvement, rather than a general
power conditioner look into something specific, "Balanced
Power". http://www.equitech.com/faq/faq.html

Well, the solution is not to put the audio gear on the UPS, but on the
direct power line. Since you don't need to keep the audio gear running
during an outage, that's fine. You put the computer on the UPS and then
all you have to worry about is the ground contamination and RF trash from
the computer grounds.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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.

Doc wrote:

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.

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.

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.

It is, but the nameplate on the back will tell you how much.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Jul 15, 8:36 am, (Scott Dorsey) wrote:

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.


Spoonfeeding needed. For example, one external drive says "Power - 12V
2A" is that what you're referring to? Am I adding up the volts or the
amps? Or both?

Doc wrote:
On Jul 15, 8:36 am, (Scott Dorsey) wrote:

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.

Spoonfeeding needed. For example, one external drive says "Power - 12V
2A" is that what you're referring to? Am I adding up the volts or the
amps? Or both?

It should say 120V, 2A.

That means 120 X 2 = 240 VA.

Add up the VA ratings and compare them with the VA rating on the UPS inverter.
The UPS will also have a watt-hour rating.

If you have a 1200 WH unit, and a 240 VA load, you can expect it to run
five hours with just that disk drive and nothing else on it.

Watts aren't the same as volt-amps, but with typical computer gear they
will be within 50%.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Spoonfeeding needed. For example, one external drive says
"Power - 12V 2A" is that what you're referring to? Am I adding
up the volts or the amps? Or both?

It should say 120V, 2A.
That means 120 X 2 = 240 VA.

Actually, I think 12V is correct. A drive doesn't draw 240VA.

I think the OP is looking at the drive case itself, not the wall wart that
powers it.

William Sommerwerck wrote:
Spoonfeeding needed. For example, one external drive says
"Power - 12V 2A" is that what you're referring to? Am I adding
up the volts or the amps? Or both?

It should say 120V, 2A.
That means 120 X 2 = 240 VA.

Actually, I think 12V is correct. A drive doesn't draw 240VA.

I think the OP is looking at the drive case itself, not the wall wart that
powers it.

If he's got drive enclosures with wall warts, he has even worse reliability
problems to worry about.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Jul 17, 8:38 am, (Scott Dorsey) wrote:

Spoonfeeding needed. For example, one external drive says "Power - 12V
2A" is that what you're referring to? Am I adding up the volts or the
amps? Or both?

It should say 120V, 2A.


Says "Power - DC Adapter 12V 2A"

Doc wrote:
On Jul 17, 8:38 am, (Scott Dorsey) wrote:

Spoonfeeding needed. For example, one external drive says "Power - 12V
2A" is that what you're referring to? Am I adding up the volts or the
amps? Or both?

It should say 120V, 2A.

Says "Power - DC Adapter 12V 2A"

Oh, that IS one of the crappy ones with the external power supply. That's
not all that useful... you want the input current numbers on the external
power supply. Or alternately you want to replace that with a more reliable
enclosure with an internal power supply...
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Jul 15, 8:36 am, (Scott Dorsey) wrote:

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.


That's another issue, I'm told that units that produce a "square"
waveform can actually damage components over time. Is this what all
the Best Buy/Circuit City type units produce? I assume there are
those that don't?

Also, I'm told there are some where the Computer runs off the unit
constantly and some where the unit only comes "online" when needed.

For example, the salesman at Cheap Guys where they currently have this
Ultra ULT31502 for $79.99

http://tinyurl.com/2r3e57

and he says it's the type where it constantly supplies power to the
computer. What about APC units like this one?

http://tinyurl.com/35ncvg


Assuming what he told me is correct, are there any inherent benefits/
problems with whether the computer is constantly running off the
battery as opposed to an "online only when needed" configuration?
Again, wondering about damage to the computer.

I like the readout on the APC case, but if one is superior at what
it's supposed to do, that's what I'd be most interested in. If the
battery is replaceable that would be great too. Even if you're only
saving 40% over the cost of a new unit, it's still 40%.

Thanks

Doc wrote:
On Jul 15, 8:36 am, (Scott Dorsey) wrote:
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.

That's another issue, I'm told that units that produce a "square"
waveform can actually damage components over time. Is this what all
the Best Buy/Circuit City type units produce? I assume there are
those that don't?

It's not as bad as a square wave, but it's close. But you don't care,
since it's a standby unit and only running off inverter when the power
goes off.

Also, I'm told there are some where the Computer runs off the unit
constantly and some where the unit only comes "online" when needed.

Everything in your price range is going to be a standby unit. If you
DO buy an online unit, you will need one that produces a nice low distortion
waveform, and that is expensive.


For example, the salesman at Cheap Guys where they currently have this
Ultra ULT31502 for $79.99

http://tinyurl.com/2r3e57

and he says it's the type where it constantly supplies power to the
computer.

This is a "line interactive" unit, which means it's a cheap standby unit
with some additional voltage regulation. That additional regulation could
turn into a noise problem, but it might also be fine. This is not a real
online UPS.

What about APC units like this one?
http://tinyurl.com/35ncvg

This is basically the same way.

Assuming what he told me is correct, are there any inherent benefits/
problems with whether the computer is constantly running off the
battery as opposed to an "online only when needed" configuration?
Again, wondering about damage to the computer.

You will not find a real online UPS at Best Buy, and you will not find one
that can produce a good enough waveform to run audio gear unless you up
your price by about two orders of magnitude.

But you don't care about that anyway, since you only want a UPS to keep
the computer from crashing during a power outage, and the cheapest of the
cheapies will do that nicely enough.

I like the readout on the APC case, but if one is superior at what
it's supposed to do, that's what I'd be most interested in. If the
battery is replaceable that would be great too. Even if you're only
saving 40% over the cost of a new unit, it's still 40%.

All of these units are cheapies, none of them are particularly well-built
or sturdy, but they will all be fine for what you want. Note that with
something in this price range, you'll be using gel cells and you should
expect to replace them about every two years for a cost that is maybe half
the cost of the total unit.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Tue, 17 Jul 2007 10:42:28 -0700, Doc
wrote:

On Jul 15, 8:36 am, (Scott Dorsey) wrote:

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.


That's another issue, I'm told that units that produce a "square"
waveform can actually damage components over time. Is this what all
the Best Buy/Circuit City type units produce? I assume there are
those that don't?

I can't tell you what Best Buy or Circuit City have.
See #4 on this page,
http://www.apc.com/solutions/display...DC4EB3FD07511D



Also, I'm told there are some where the Computer runs off the unit
constantly and some where the unit only comes "online" when needed.

Yes but be careful of your terms, since the type where the
computer runs off the unit constantly, meaning it's inverter
is always supplying the power to the (powered) equipment is
sometimes called an "online" UPS.



For example, the salesman at Cheap Guys where they currently have this
Ultra ULT31502 for $79.99

http://tinyurl.com/2r3e57

That looks like a good deal for $80. I don't know if it's a
good quality product or not, nor what your total load will
be so as to determine if the capacity is enough per powered
period.



and he says it's the type where it constantly supplies power to the
computer. What about APC units like this one?

http://tinyurl.com/35ncvg

Are you intent on buying one locally? Given the internet
you can really pick and choose exactly what you're getting.




Assuming what he told me is correct, are there any inherent benefits/
problems with whether the computer is constantly running off the
battery as opposed to an "online only when needed" configuration?
Again, wondering about damage to the computer.

The whole point is that your computer should be safe, or at
least in no more jeopary, using either type than not.
Remember they are intended to power a computer. Even so,
the computer would be more immune to AC mains problems when
the UPS is an online type or "running off the battery" as
you put it (which is a bit of a misconception as the UPS is
actually running the computer off the inverter which
receives power from a subsequent power stage that also
happens to (provide the power towards) charge the battery.




I like the readout on the APC case, but if one is superior at what
it's supposed to do, that's what I'd be most interested in. If the
battery is replaceable that would be great too. Even if you're only
saving 40% over the cost of a new unit, it's still 40%.


Generally the battery is a non-issue, pop it open (making
sure it's turned off first) and note the battery voltage,
capacity, size and terminals size. They tend to use common
battery sizes so you can buy a replacement online if it
isn't available locally.

Also, I'm told there are some where the computer runs off
the unit constantly and some where the unit only comes
"online" when needed.

I explained that in my previous posting. It's called a UPS -- an
uninterruptable power supply.

The device we commonly call a UPS is actually an SPS -- a standby power
supply.

On Jul 14, 8:05 pm, Doc wrote:
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.

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_Smar...A.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

On Jul 15, 11:28 am, wrote:

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

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.

"Mike Rivers" wrote in message ps.com...
On Jul 15, 11:28 am, wrote:

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

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.

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

On Jul 15, 7:40 am, Mike Rivers wrote:
On Jul 15, 11:28 am, wrote:

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

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.

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

On Jul 15, 1:22 pm, wrote:

The Kill-A-Watt will measure VA or Watts and also power factor in
addition to volts and amps.

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.

In article . com,
Mike Rivers wrote:

On Jul 15, 1:22 pm, wrote:

The Kill-A-Watt will measure VA or Watts and also power factor in
addition to volts and amps.

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.

Mike-

The Kill-A-Watt is made (or imported?) by P3 International,
http://www.p3international.com/produ.../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

On Jul 15, 10:39 am, Mike Rivers wrote:
On Jul 15, 1:22 pm, wrote:

The Kill-A-Watt will measure VA or Watts and also power factor in
addition to volts and amps.

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.

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

"Mike Rivers" wrote in message
ups.com...
On Jul 15, 1:22 pm, wrote:

The Kill-A-Watt will measure VA or Watts and also power factor in
addition to volts and amps.

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.


And for determining the load on the UPS, its the VA of the attached
equipment that you need to know. While its the watts that influence the
running time, if the VA rating is exceeded, then either the over current
protection will operate of the inverter transformer or its driving circuitry
may burn out.

On 7/15/2007, posted this:
On Jul 15, 7:40 am, Mike Rivers wrote:
On Jul 15, 11:28 am, wrote:

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

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.

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

The Kil-A-Watt also will accumulate KWH (kilowatt hours), which I find
useful, such as if you have a computer that is sometimes sleeping and
sometimes running - or a device like a refrigerator, which also is only
on part-time.

--
Gene E. Bloch (Gino)
letters617blochg3251
(replace the numbers by "at" and "dotcom")

On Sat, 14 Jul 2007 21:05:41 -0700, Doc wrote:

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.

I wanted an extremely high quality UPS for my computer at work.
I bought a Tripplite SU750XL. This is a 750VA pure sine wave
double conversion tower unit. Maintains voltage +/-2%, zero
switchover time. Probably can't get better isolation from the power
line. This is their smallest double-conversion unit. Goes for about
$350. The downside is the fan. It has a loud fan that runs
constantly, even when all loads are disconnected.

Steve Noll | The Used Hi Tech Equipment Dealer Directory:
| http://www.big-list.com
| Peltier Information Directory:
| http://www.peltier-info.com

"Doc" wrote in message
oups.com
I've got two computers - a PIV and a PIII that share a
monitor. I use them primarily for doing audio/video.

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.

What is "a while" in minutes?

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?

They are good enough for their intended purpose, which may or may not be
what you have in mind.


What are important features to look for?

Primarily, enough capacity to keep your computers running for "a while".

These
various units have charts indicating how long they should
power a computer, but I don't know how realistic they
are.

The specs are probably realistic, as long as the internal batteries are in
good shape.

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.

Consult the specs. Key to this is knowing the actual power drain of your
computers while they are doing the job you have. I'd recommend a small
investment ($30) in a little device called a "Kill-o-watt", to get some
actual numbers.

I usually turn off the monitor when rendering video, it's
my understanding the monitor is a big power hog.

That's right. Things like video monitors and laser printers are good things
to run direct off the power line, and not off the UPS.

"Arny Krueger" wrote in message
. ..
"Doc" wrote in message
oups.com

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.

What is "a while" in minutes?


It seems frequently these short outages come in clusters so a lot of this
would be on a judgement-call basis but off the cuff, I suppose I'd like it
to be able to keep them both going for 10 minutes - say if the power isn't
back on in 5, it gives me 5 minutes to close things down and shut down,
which should be plenty with time to spare. Playing the percentages, it's
more likely I would only be running one of them but you never know.

If the outage occurs when a lightning storm can be heard approaching, I'd be
shutting down and unplugging anyway. Unless I'm very sure it's going to be a
storm-free day, I typically unplug everything including the modem when
leaving for work or for a protracted period.

On Jul 14, 9:05 pm, Doc wrote:
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.

I use the one that comes in the big brown van.

Jim Williams
Audio Upgrades

On Wed, 18 Jul 2007 10:42:42 -0700, "nappy" wrote:

C'mon nappy. Don't keep as all so excited!
What's on your liver?

-m-

Martin Heffels wrote:
On Wed, 18 Jul 2007 10:42:42 -0700, "nappy" wrote:

C'mon nappy. Don't keep as all so excited!
What's on your liver?


Maybe his laptop died and that's all that shows on the screen ...?


geoff

"Geoff" wrote ...
Martin Heffels wrote:
On Wed, 18 Jul 2007 10:42:42 -0700, "nappy" wrote:

C'mon nappy. Don't keep as all so excited!
What's on your liver?


Maybe his laptop died and that's all that shows on the screen ...?

Funny(?) you should mention that.
MY laptop died this morning and shows nothing on the screen.
It starts OK, with the MSwin logo on the black screen and the
"progress" bar, but as soon as it flips into the native resolution,
the screen goes dead. This may be the first time I have booted
it since one of those automatic MS "patches" or "upgrades" or
whatever.