Power Outage

[Jay567]

How bad are power outages to a pc? Do frequent power outages damage a pc? I have a APC power bar... does this help?

Thanks.

 

[pkme2]

Get a AVR (automatic voltage regulator) for your pc.
For us here in Hawaii, we get power outages, brownouts, earthquakes (2 more today) and the fluctuations on our power lines surely wreaks havoc on our pc's.
If you don't have these problems, well its up to you.
Many of the UPS backups come with AVR built in. At least, I'm happy with the results. No more burnt out pcs.

 

[Navid]

If you have a power outage, your PC will turn off. If this happens while the hard drive is being accessed, I suppose it is possible to have data corruption.

When power comes back, you could have damage too!

If line voltage does not completely go down to zero, you have what is called "Brown-out". That could cause problems too specially if the power supply shows unexpected behavior.

No, a power bar does not do any good for a power outage. A UPS does.

 

[Jay567]

can you suggest one that isn't too expensive and good for home use?

 

[pkme2]

I recommend Cyberpower

I ihave a 1250V with AVR for 3 computers.
You may use a 685V w/ AVR for one.

These backups are very popular here on Maui since we had those blackouts.

 

[Navid]

Not knowing which country you live in, since you have not made your profile visible, makes it difficult for many to make a useful recommendation.

 

[Jay567]

i am in canada.

 

[azandertt]

Originally posted by: pkme2
I recommend Cyberpower

I ihave a 1250V with AVR for 3 computers.
You may use a 685V w/ AVR for one.

These backups are very popular here on Maui since we had those blackouts.

I live in one of those houses that the power goes out every time my wife turns on the hair dryer and I had to pick up a UPS. I've also had success with Cyberpower.

 

[Navid]

I live in the US and APC is my choice.

I know many large companies use APC for all of their computers both in Canada and the US. That tells me that APC must have a healthy customer service policy and practice it.

For a home PC, a standby UPS is all you need. Select it in such a way that it would give you a 5-7-minute runtime. Set it up to shut down programs and the PC in case the power is lost for long enough time that the estimated remaining runtime is less than 2 minutes.

http://apc.com/tools/ups_selector/index.cfm
This page makes selections based on your PC and monitor etc.
Click on "Configure Now" under "PC or Workstation".

http://apc.com/products/runtime_for_extendedruntime.cfm?upsfamily=21
This is a runtime chart showing how long the unit runs with no power with different amount of load.

Keep in mind that the battery ages and dies after a few years (3). Even if the unit is sitting on a shelf in a store, the battery still ages. I got my BE725BB unit from Circuit City in the US and tested its runtime by measuring how long it ran loaded on a 100W lamp and found out that its runtime was shorter than stated. Contacted APC. They sent me a replacement and paid for shipping label for me to send mine back to them.

APC has a 2-year warranty including the battery.

AVR (Automatic Voltage Regulation) is a good thing for an extremely sensitive equipment. For a home PC, it is not necessary. Basically, your unit will switch to battery if the line voltage drops below a threshold and restores the voltage that is supplied to the PC. This happens really fast. The PC power supply should function properly considering that there are large capacitors at the output of the PSU, which will not allow the output voltage of the PSU to drop too much.

There are some power supplies that cannot tolerate a slight drop in their input voltage. One example is the old single-rail 480W TAGAN. It would shut down the PC, in a power outage, even on a UPS. That is known by TAGAN and they replace them.

All of this is based on a regular home PC environment and application. If you have a mission-critical computer, things will be different.

 

[Jay567]

Do you think the ES line of APC is sufficient? I don't care how long my computer is running for after a power outage... I just don't want it to screw up my computer.

 

[Navid]

Clarify what you mean by "sufficient".

You can select different size units in each line. The size determines the runtime if that's what you mean by sufficient. You can get BE325, which runs for only 7 minutes with a small 100W load (not recommended), and you can get BE750BB, which runs for 7 minutes with a 400W load.

The runtime decreases gradually as the battery ages.


You can get units that offer higher levels of functionality. For example there is a different class of UPS that always runs off of battery! Even if the line voltage is what it is supposed to be, the UPS still runs off of battery. It charges the battery continuously and the battery creates the output voltage. So, if there is a power outage, there will not be a glitch in the output voltage. This is necessary for extremely sensitive equipment. This is not going to be as cheap as the ES line.


The ES line is the cheapest which I think has what a basic home PC needs, keeping the PSU happy for a few minutes after power outage or sever brown out and signaling the PC that the battery is getting low so that the PC can shut down gracefully.

 

[Jay567]

Thanks for the help Navid. I think I'll either get the ES 350 or 500VA model.... The 350 gives about 2 minutes of battery backup and the 500 gives about 10 minutes... Do you think 2 minutes is enough time to power down everything so my computer is nice and safe?

 

[Jay567]

Sorry... one last question... I still don't completely understand the extent of damage that my computer can incur due to a blackout. Say I get 1 blackout a week... what kind of damage can I expect? Can my computer become a total writeoff?

Thanks for all your help.

 

[Navid]

Originally posted by: Jay567
Thanks for the help Navid. I think I'll either get the ES 350 or 500VA model.... The 350 gives about 2 minutes of battery backup and the 500 gives about 10 minutes... Do you think 2 minutes is enough time to power down everything so my computer is nice and safe?

That is if your power requirement is only 200W. Is that what you think your power usage is?
Have you taken into account your monitor?

2 minutes is enough. However, that time decreases as the battery ages.

 

[WobbleWobble]

Asides from the obvious consequences of a blackout such as losing your work before you save it and possible data corruption (when the write cache hasn't had a chance to write all the data from its buffer), your computer can be a total writeoff. It's possible that during a blackout, you may get power surges that could wreak havoc with sensitive electronics like computers. At the very least, you should have a surge protector. Simply losing power should do no damage to your hardware.

Now, since you're from Canada I'd suggest looking out for Boxing Day sales. Most of my UPSes have been bought from Boxing Day sales at more than 50% off (APC & Cyberpower). I know that my local Canadian Costco also carries a APC UPS.

 

[Navid]

Originally posted by: Jay567
Sorry... one last question... I still don't completely understand the extent of damage that my computer can incur due to a blackout. Say I get 1 blackout a week... what kind of damage can I expect? Can my computer become a total writeoff?

I cannot answer that with a figure because I do not have statistical data.

Sometimes the problem actually occurs when the power comes back! The voltage could spike higher than normal in that case. It shouldn't. But, it does sometimes. Then, a UPS can take care of that too. The UPS disconnects the PC from the line and provides voltage to the PC using the battery when the line voltage is too low or too high.

Too high an input voltage to the power supply could damage it. A damaged power supply could damage any component in the PC.

 

[Bob Anderson]

Originally posted by: Navid


You can get units that offer higher levels of functionality. For example there is a different class of UPS that always runs off of battery! Even if the line voltage is what it is supposed to be, the UPS still runs off of battery. It charges the battery continuously and the battery creates the output voltage. So, if there is a power outage, there will not be a glitch in the output voltage. This is necessary for extremely sensitive equipment. This is not going to be as cheap as the ES line.

Yep, all medical grade UPS's work that way. In geek parlance they are known as 'on-line' or 'dual-conversion' UPS's. The AC power sent to the PSU is actually regenerated anew from the DC supplied by the battery. Because the battery is constantly being charged, they consume more wall AC than the conventional battery back up type.

I have one, and yes they are very expensive. It consumes 30 - 32 watts all by itself, as long as it is plugged in. But this type is not necessary for a home computer user. I bought one because I'm a technology nut with too much spare cash. Bad combination.

-Bob

 

[Jay567]

i already have an apc surge protector... is this enough? i think i'm a pretty average pc user... i have data that i don't want to lose but i have an external hard drive to back it up on... will my hardware see any significant damage due to a blackout? do i really need a ups?

 

[Bob Anderson]

Originally posted by: Jay567
i already have an apc surge protector... is this enough? i think i'm a pretty average pc user... i have data that i don't want to lose but i have an external hard drive to back it up on... will my hardware see any significant damage due to a blackout? do i really need a ups?

It would be safer if you had one. Plug your computer, monitor and external hard drive in to it.

Go to any UPS manufacturer's site and do the size configurator. Since you have an APC surge protector, start with that company. You want at least 5 minutes reserve time on the UPS battery to safely shut down in the event of a power failure.

-Bob