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Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
"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 |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
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? |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
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." |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
Most UPSes come with companion software that provide
for automatic shutdown, or after an interval you specify, or upon battery exhaustion. 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. |
Thoughts, tips, suggestions on what UPS to use?
"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 |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
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. This is why the companion software of the UPS is better. It's more sophisticated than the built-in Windows management. 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. |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
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). |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
On Jul 16, 3:03 pm, Fred McKenzie wrote:
The Kill-A-Watt is made (or imported?) by P3 Yes, I eventually figured that out. Home Depot has a P3 Kill-A-Watt listed on their web site (haven't checked in the store yet). It looks the same as the 4400 that seems to be common to the web sellers, but it's a different model number. 9034. Also a bit more expensive than the web sellers, but less than $10 difference when you add in the expensive shipping. If they have it in the store, I'd just as soon buy it there for the convenience of returning it if I'm not impressed. I don't really need it, but it's cheap enough to have handy in case I want to know how much power something is taking. |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
In article . com,
Mike Rivers wrote: Yes, I eventually figured that out. Home Depot has a P3 Kill-A-Watt listed on their web site (haven't checked in the store yet). It looks the same as the 4400 that seems to be common to the web sellers, but it's a different model number. 9034. Also a bit more expensive than the web sellers, but less than $10 difference when you add in the expensive shipping. If they have it in the store, I'd just as soon buy it there for the convenience of returning it if I'm not impressed. Mike- I prefer to buy locally, so searched everywhere for one. So far, the web stores are the only ones I've found that carry them. I did try a couple of Home Depots. The 9034 number might be Home Depot's internal stock number for the 4400. I found a one-page PDF instruction sheet for the 4400 on line, but don't recall where. It may have been at the P3 web site. There is a review at http://www.redjar.org/jared/projects...y/kill_a_watt/ with some additional links. Fred |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
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? |
Thoughts, tips, suggestions on what UPS to use?
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." |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
"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. |
Thoughts, tips, suggestions on what UPS to use?
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" |
Thoughts, tips, suggestions on what UPS to use?
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." |
Thoughts, tips, suggestions on what UPS to use?
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." |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
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." |
Thoughts, tips, suggestions on what UPS to use?
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 |
Thoughts, tips, suggestions on what UPS to use?
|
Thoughts, tips, suggestions on what UPS to use?
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." |
Thoughts, tips, suggestions on what UPS to use?
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. |
Thoughts, tips, suggestions on what UPS to use?
Scott Dorsey wrote:
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 Of cause. I was partly referring to the OP doing both audio and video on those computers, so other gear might be hooked up - which it shouldn't. Then again, I was also thinking of forces of nature et al.., as it was suggested some UPS's may provide some added protection against such. While I live in an appartment surrounded by reasonable large buildings having measure against ligtning installed, nevertheless 'interesting' currents can creep around. I'll do something else against that.. -- Kind regards, Mogens V. |
Thoughts, tips, suggestions on what UPS to use?
On 17 Jul 2007 14:13:37 -0400, (Scott
Dorsey) wrote: 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. Yes but I'm saying, if it's important you can't just randomly pick audio gear, this is one of many criteria in discriminating what gear to use, and what existing gear should be replaced or tweaked a bit in the power supply subcircuit. 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're right, "I" don't need it to run during an outtage, but sometimes I feel I "want" at least a headamp and MP3 player running off batteries. However, some may really "need" to keep running during an outtage. For example I used to work as an engineer at a radiosStation and it was certainly true then, but there were generators not $50 battery powered UPS. Another example would be a recording studio, or a PA system at a department store to direct customers... there are too many possible scenarios to really see all possible situations when audio gear might need to be working during an outtage, but I do feel a lower end consumer UPS isn't usually the answer. 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 That's never a concern, the switching PSU used in a computer have far more output noise than what little would remain from an UPS with non-sine output, as is the noise created by multiple high current circuits in a typical computer system. |
Thoughts, tips, suggestions on what UPS to use?
"kony" wrote ...
You're right, "I" don't need it to run during an outtage, but sometimes I feel I "want" at least a headamp and MP3 player running off batteries. However, some may really "need" to keep running during an outtage. For example I used to work as an engineer at a radiosStation and it was certainly true then, but there were generators not $50 battery powered UPS. The studio audio equipment is trivial compared to the power it takes to keep the transmitter running, even at reduced output. Another example would be a recording studio, If I were a commercial recording (or video) studio reliant on computer-based recording, I would keep at least the recording computer on UPS (but not necessarily the audio equipment, preamps, mixer, monitor amp/speakers, etc.) just enough to save whatever recording was in process. If there is some necessity to keep recording during power outages, that is an entirely different scenario with different (and much more expensive) possible solutions. or a PA system at a department store to direct customers... Life/Safety Systems, particularly for public buildings have requirements for some kind of operability during power interruptions. That was something designed into the system by the architect and engineers, etc. The fire alarms (audible & visible) and emergency lighting (including EXIT signs) are usually the primary concern to aid evacuation. |
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