Can you guys tell me about UPSs?

skull

Platinum Member
Jun 5, 2000
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327
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I had I guess what would you call a brown out a few weeks ago. Computer dropped out but stayed on, lights dimmed, blower motor slowed stopped started slowed. I ran out to the truck grabbed a volt meter by the time I got it out everything was back to normal.

Guessing it was an under voltage. This isn't a regular occurence but I'm looking to protect the computer. I take it a UPS is the way to go.

I'm looking at this one. http://www.amazon.com/Tripp-Lite-ECO...pr_product_top

I have 80w phenom with an ssd on a corsair 400w power supply. I take it its a good idea to protect my new monitor the input on its power supply is 180 watts. Is this too much for a 425w UPS? I'm sure neither draw close to rated I can take amp draw readings if need be.

I don't need a long battery life at all just something to protect my stuff. Any recomendations for less then $100?

Can have this thing shutdown the computer? I run ubuntu what if its in suspend? If the power goes off and im not home will the UPS just kill power when it drops to a certain voltage or does it make a dangerous under voltage situation too.

Also not sure if this outlets grounded my apartment is a mixmatch of grounded and ungrounded circuits. I can run a grounded circuit if its neccesary.
 

Blain

Lifer
Oct 9, 1999
23,643
3
81
* Buy as much capacity as you can afford (don't worry about "sizing")
* Buy an AVR (automatic voltage regulation), unit
 

Tristor

Senior member
Jul 25, 2007
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You need to ensure the USP unit has "true sinewave" or "pure sinewave" rather than "stepped approximation of a sinewave" in order to enable the use of Active PFC power supplies (almost all good power supplies have Active PFC anyway, so unless you have crappy PSUs you probably have Active PFC whether you know it or not). Otherwise when you connect your computer you'll find it will not turn on and will be wondering why. This is because an Active PFC power supply cannot be powered properly by a stepped approximation sine wave.
 

Blain

Lifer
Oct 9, 1999
23,643
3
81
You need to ensure the USP unit has "true sinewave" or "pure sinewave" rather than "stepped approximation of a sinewave" in order to enable the use of Active PFC power supplies (almost all good power supplies have Active PFC anyway, so unless you have crappy PSUs you probably have Active PFC whether you know it or not).

Otherwise when you connect your computer you'll find it will not turn on and will be wondering why.
This is because an Active PFC power supply cannot be powered properly by a stepped approximation sine wave
.
:colbert: Wrong...
Modified/Simulated sine wave UPS will power an Active PFC PS just fine.
 
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Zeldak

Member
Nov 6, 2005
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I bought a "CyberPower" brand UPS at Costco last year for $89.99. I thought of it as high end surge protector. It was supposed to provide 30 min of computer backup time. Four days ago the city power went out at the pole outside our house. It took almost 3 hours for the city to fix. I didn't try to start our main CPU--didn't need to.

This represented a situation I hadn't thought of, but the entire outage time, three of us used wi-if iPads constantly and I used a laptop for an hour. I had a super important video call from work. With cordless phone and routers powered by the UPS, there was NO HINT of connectivity problem. It was as if our power hadn't even gone out.

The Costco "CyberPower" unit paid for itself several times over in that one episode. I'd buy it again tomorrow at twice the price. You might consider it.
 

Zeldak

Member
Nov 6, 2005
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Oh, yeah: shutdown. You can set these things with their included software to shut your system(s) down as quickly or gently as you like.
 

Torn Mind

Lifer
Nov 25, 2012
12,052
2,766
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:colbert: Wrong...
Modified/Simulated sine wave UPS will power an Active PFC PS just fine.

Okay sure... I'll just leave this here: http://www.jonnyguru.com/forums/showthread.php?t=3964

Perhaps it's because I strongly prefer Enermax PSUs in my own builds, but my own personal experiences also indicate that Active PFC PSUs prefer if not outright require true sine wave output. Good luck either way.

Some modified/simulated sine wave UPS units are incompatible with some Active PFC units, but other units function perfectly well, although PSU might make some noise due to the modified sine save. I have a modified sinewave unit powering and an original Antec Earthwatts, a PSU in which there were reported instances of UPS incompatibility, but not with the Cyberpower CP685AVR unit that has supposedly been on sale on Amazon since 2004. It cost $50 less than the cheapest pure sine wave unit in the Cyberpower CP850PFCLCD, although other features like the LCD screen and other information are also not present on the CP685AVR. I bought the UPS at Staples, so returns wouldn't incur sunk costs for me.

I don't intend to run a computer off a UPS for any extended period of time, so the brief time the PSU is subjected to a non-sine wave should not cause it harm. True sine wave is fine to get if you want to run the computer off of it for a prolonged period, if you don't want to deal with the hassle of returning an incompatible item, or if you're attaching other equipment that could use it, such as audio devices or TVs.
 

westom

Senior member
Apr 25, 2009
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I don't intend to run a computer off a UPS for any extended period of time, so the brief time the PSU is subjected to a non-sine wave should not cause it harm.
Nobody implied 'harm' is created. Only most extreme active PFC circuits are upset by modified sine waves (also called by some manufacturers a pure sine wave). Most do not have such circuits which is why Blaine is correct. It will work just fine.

If you have that rare exception, then the computer simply powers off. No damage.

Low voltages also do not cause damage. Good voltage for a computer is even when incandescent bulbs dim to 40% intensity. If voltage drops lower, then electronics simply power off. Again, no damage.

Voltage dropping that low is not harmful to electronics. But can be harmful to motorized appliances. If worried about low voltage, then get a UPS, AVR, etc for appliances at greater risk including the refrigerator, furnace, and dishwasher.

More important is the reason for that brownout. In most cases, it is irrelevant. In rare cases, a brownout may indicate a serious problem. Sometimes a human safety issue if a brownout is due to wiring problems inside the house. IOW solve that rare problem rather than cure symptoms with a UPS.
 

Red Squirrel

No Lifer
May 24, 2003
70,225
13,608
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www.anyf.ca
:colbert: Wrong...
Modified/Simulated sine wave UPS will power an Active PFC PS just fine.

Yeah seems to me this would be a much bigger issue that you'd hear more about. Most home grade UPSes in the $100 range arn't pure sine.

When did PFC started being a thing? I can confirm that all my servers run fine on my stepped square wave UPS. Though most of those machines are fairly old.

That said I'd recommend a 1000VA unit. Seems to be best bang for the buck. Once you go higher then it starts to get more expensive. Typically the higher the rating the bigger battery it will have too, so under small load you'll get more run time. It's nice to get like 15-20 minutes so you can ride through a short outage and continue doing what you were doing. Just don't let it drop hard since that's very hard on the computer and kinda defeats the main purpose of the UPS. :p
 

Torn Mind

Lifer
Nov 25, 2012
12,052
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Nobody implied 'harm' is created. Only most extreme active PFC circuits are upset by modified sine waves (also called by some manufacturers a pure sine wave). Most do not have such circuits which is why Blaine is correct. It will work just fine.

If you have that rare exception, then the computer simply powers off. No damage.

Low voltages also do not cause damage. Good voltage for a computer is even when incandescent bulbs dim to 40% intensity. If voltage drops lower, then electronics simply power off. Again, no damage.

Voltage dropping that low is not harmful to electronics. But can be harmful to motorized appliances. If worried about low voltage, then get a UPS, AVR, etc for appliances at greater risk including the refrigerator, furnace, and dishwasher.

More important is the reason for that brownout. In most cases, it is irrelevant. In rare cases, a brownout may indicate a serious problem. Sometimes a human safety issue if a brownout is due to wiring problems inside the house. IOW solve that rare problem rather than cure symptoms with a UPS.
Blain is incorrect because his statement uses no qualifier such as "all", "most", "some", "none", etc for his statement. With no such qualifier, it is implied that he meant all modified sine wave units can function when paired up with any unit that is PSU.

The "harm" I mentioned has nothing to do the matter about PSU with active PFC functioning with modified sine save UPS; it will work, won't power on when power is cutoff, or it reboots when power switches over, none which is results in actual damage. I mentioned "harm" in a separate paragraph and specifically said what exactly can cause this (potential) harm, which is applying non-sine waves to components with in the PSU for an extended period of time. In addition, where have I mentioned low voltage as the cause of harm? Indeed, the potential harm I'm talking about is about the effects, if there are even any, of non-sine wave of the current going through certain components in the PSU prior to being filtered in the secondary; the computer itself is safe as long the PSU is not one of those garbage ones.

Ultimately, if you want to rebut me go ahead. But it better be about what I actually said, which is about applying a modified sine wave to components within the PSU and harming said components. I myself am not sure that a modified sine wave actually does anything harmful to a capacitor, resistor, diode, etc, so I'm all open to a well-grounded explanation saying why it isn't harmful just as I'm open to a well-grounded explanation that it is.


As for low voltage, of course the PSU can run anywhere between 90-240 volts. That's why one can use many PSUs in Japan, where many houses have 100V wall output. That's not the point of AVR, which is to control rapid change in voltage as well as keep it from going out of a safe range, usually above the 120 volts.
 

Torn Mind

Lifer
Nov 25, 2012
12,052
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Yeah seems to me this would be a much bigger issue that you'd hear more about. Most home grade UPSes in the $100 range arn't pure sine.

When did PFC started being a thing? I can confirm that all my servers run fine on my stepped square wave UPS. Though most of those machines are fairly old.

That said I'd recommend a 1000VA unit. Seems to be best bang for the buck. Once you go higher then it starts to get more expensive. Typically the higher the rating the bigger battery it will have too, so under small load you'll get more run time. It's nice to get like 15-20 minutes so you can ride through a short outage and continue doing what you were doing. Just don't let it drop hard since that's very hard on the computer and kinda defeats the main purpose of the UPS. :p

PFC became a thing because it helps the power company and the environment, which helps the rest of the populace indirectly. It is something folks in the industrial sector would know, because power companies actually charge them for the "unusable" power. Of course, one must consider the cost of adding the extra circuitry, but I speculate that it is less than the power "lost" due to a low power factor.

http://en.wikipedia.org/wiki/Power_factor#Active_PFC
 

westom

Senior member
Apr 25, 2009
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0
71
In addition, where have I mentioned low voltage as the cause of harm? Indeed, the potential harm I'm talking about is about the effects, if there are even any, of non-sine wave of the current going through certain components in the PSU prior to being filtered in the secondary; the computer itself is safe as long the PSU is not one of those garbage ones.

First a low voltage myth was stated (or implied) by others including in the original post. Irrelevant is who made (implied) the claim. Damage due to low voltage is a popular myth promoted only by fear and often by many who do not even know what electronic parts do.

Second, if a non-sine wave is harmful to certain components over a long term, then specially cited is the 'at risk' component. I have been doing this stuff as a designer for too long. Have seen so many 'experts' who never did this stuff; never built an electronic circuit. They often do not know simplest electrical concepts such as current and voltage source. I still cannot find an electronic part damaged by that type of power. But I read so many who 'fear' harm only because hearsay and no electrical knowledge says so.

No low voltage from zero to full voltage causes damage. Overvoltages can do damage. Industry charts for what electronics must withstand without damage goes up to 600 volts (for 120 volt appliances). Good AVR is what a power supply does. But so many fear myths about destructive 130 volts to 120 volt appliances. Then promote these expensive AVR solutions - because AVR manufacturers told them to fear.

Third, short voltage variations, some call them spikes, are made irrelevant by protection routinely found in PSUs. Concern are rare spikes that would blow through that AVR. These rare events (maybe once every seven years) are best averted elsewhere. What are these fast voltage variations that cause long term hardware damage? Specifically defined by volt, current, and rise time numbers.

OP asked about harm created by a brownout. That is the topic. No such harm exists. Either electronics work perfectly happy. Or powers off when voltage drops too low. If a computer has extremely robust active PFC (maybe exceeding 98%), then 'dirty' UPS power may confuse that circuit. So that computer simply powers off. No damage.

UPS power can be so 'dirty' as to harm small electric motors. That same 'dirty' UPS power is also good for all electronics. UPS does not protect hardware. UPS is to protect unsaved data.

PFC was made popular or necessary by strict European requirements.
 

imagoon

Diamond Member
Feb 19, 2003
5,199
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0
Modified sign wave is also just a class of inverters. You need to look specifically at the level count. A 3 step modified sign wave is cheap to produce but is the least compatible wave. Here is a random example of many more stepped sine wave inverter:

http://www.solarray.com/TechGuides/Inverters_T.php

Better UPS units will use those types of inverters and most Active PFC units won't even be able to tell the difference in the higher step counts due to the capacitors filtering the steps.
 

thedosbox

Senior member
Oct 16, 2009
961
0
0
Okay sure... I'll just leave this here: http://www.jonnyguru.com/forums/showthread.php?t=3964

Perhaps it's because I strongly prefer Enermax PSUs in my own builds, but my own personal experiences also indicate that Active PFC PSUs prefer if not outright require true sine wave output. Good luck either way.

You should have read through the thread:

http://www.jonnyguru.com/forums/showthread.php?t=3964&page=5

Okay -- here is a follow-up response from the Silverstone engineer in Taiwan (with good news for those of us in the US.)

"It is fine if you living in US and used 120V input in your OP700, even by a not pure sineware UPS."

In other words, use whatever UPS you want if you're living in North America (or anywhere that runs 110-120V).
 

thedosbox

Senior member
Oct 16, 2009
961
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I'm looking at this one. http://www.amazon.com/Tripp-Lite-ECO...pr_product_top

I have 80w phenom with an ssd on a corsair 400w power supply. I take it its a good idea to protect my new monitor the input on its power supply is 180 watts. Is this too much for a 425w UPS? I'm sure neither draw close to rated I can take amp draw readings if need be.

I don't need a long battery life at all just something to protect my stuff. Any recomendations for less then $100?

Can have this thing shutdown the computer? I run ubuntu what if its in suspend? If the power goes off and im not home will the UPS just kill power when it drops to a certain voltage or does it make a dangerous under voltage situation too.

Connecting the UPS via the USB cable will allow a Windows machine to shut itself down after a pre-determined period on the UPS. I've got a 550VA Cyberpower UPS for this very purpose, and it provides enough juice to allow for an orderly shut down.

Not a Linux user, but it looks like Ubuntu has some UPS support for similar functionality. No idea if it's restricted to APC UPS's though