Storm and lights dimming - pc still on

sewerino26 · 6 Oct 2017 at 22:06

Hello. I have an question. There was a storm in my country yesterday. Power was on . But there was random 1 second lights dimming in my house. was still on, and was still on. So why both computers was on and wont turns off when lights was dimming? Thanks. And is this harmful to pc?
How can i check that nothing damage in my pc?
Ah i dont have UPS.

Psu is Corsair 750RM and MB: Asus Z170-P

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Steampunk · 6 Oct 2017 at 23:02

You had a slight dip in your supply, likely the storm affecting the power supply network, possibly a lightning strike on a cable or substation (or near miss), or a tree blowing over and taking a power cable out. Your PC and laptop have big capacitors in the PSUs and your laptop also has a battery that might be able to take up any slack when the power dips. This makes them slightly more resistant to brown-outs than lightbulbs.

It's not good for the PC, but the most likely outcome is your PC crashes, and you can have dataloss from the disk or SSD crashing when you're using it and getting a corrupted file system. If you're going to get a lightning hit or near miss, then no PC will survive that. It's a billion volts that's just jumped three miles through the air. A UPS won't do a lot to stop any strike that's too near.

If you have a big storm with lots of lightning, it's best to unplug any computers, and that includes any phone/cable lines that might get hit outside and zap your hardware.

sewerino26 · 6 Oct 2017 at 23:05

So how can i be sure that nothing wrong with my pc? ( Pc not turned off during storm, laptop not turned off, and laptop is without battery )

There was only light flickering in house at random moments for 1 second,

Steampunk · 6 Oct 2017 at 23:32

sewerino26 said:
So how can i be sure that nothing wrong with my pc? ( Pc not turned off during storm, laptop not turned off, and laptop is without battery )

There was only light flickering in house at random moments for 1 second,

Why would there be anything wrong if nothing happened but your lights flickered? If you haven't seen a problem or error message, then there's nothing to be worried about. A momentary dip in power that didn't even reboot your PCs is not a problem unless it's happening all the time.

EsaT · 7 Oct 2017 at 17:06

Steampunk said:
Your PC and laptop have big capacitors in the PSUs

PSU's primary capacitance is enough for ~16 ms by ATX spec.
Cheap PSUs might not even handle 10 ms power cut, while Seasonic Primes handle IIRC ~30ms.
But if voltage just sags active-PFC keeps good PSU operating down to ~100V as byproduct of its primary function.

And funnily while writing that just had short power cut blinking lights.
But that's why there's Eaton 5P 1550i 1,1kW sinewave UPS next PC...

Sasahara · 17 Oct 2017 at 23:50

Further reading to EsaT's correct answer.

Hold up time it the general term for this.

http://blog.fsp-group.com/en/the-importance-of-hold-up-time/

w1ze1 · 21 Oct 2017 at 21:41

My PC keeps going but my VM HUB 3 reboots as its crap and probably not as many Caps holding some power, slow as hell to come back online also.

neil_g · 22 Oct 2017 at 18:14

EsaT said:
But that's why there's Eaton 5P 1550i 1,1kW sinewave UPS next PC...

i had 3 days of brownouts recently, my APC was complaining that the input was low and needed to keep boosting the power. was bouncing around all over, averaging about 215V and dipped as low as 195V several times.

contacted the local power company to be told they could not see any issues. kept on at them as the UPS really wasn't happy, sent them graphs from powerchute etc. eventually they sent engineers to the local substation who funnily enough found an "issue with [their] equipment which would have been causing the voltage issue".

thankfully the UPS did it's job and kept my arrays safe.

never did get an apology or full explanation from the power company.

Phil2008 · 28 Oct 2017 at 22:07

neil_g said:
i had 3 days of brownouts recently, my APC was complaining that the input was low and needed to keep boosting the power. was bouncing around all over, averaging about 215V and dipped as low as 195V several times.

contacted the local power company to be told they could not see any issues. kept on at them as the UPS really wasn't happy, sent them graphs from powerchute etc. eventually they sent engineers to the local substation who funnily enough found an "issue with [their] equipment which would have been causing the voltage issue".

thankfully the UPS did it's job and kept my arrays safe.

never did get an apology or full explanation from the power company.

You should have got a bit of money for your findings out.. hehe

Hey guys I have noticed nowaday during a thunderstorm if we get big bangs, a few seconds before the bang the power goes off...... Why is this, as years ago the power would either stay on or the bang would trip it off in the house?

Steampunk · 28 Oct 2017 at 22:13

Lightning happens before the thunder. Sounds like you are getting a near strike and then hearing the thunder a few seconds later. You'd have to look at changes in your house or in the local supply to guess why a near strike is shutting off your power where it didn't before. It would help if you knew exactly why and where the power is shutting off - maybe an issue with a local substation?

Phil2008 · 28 Oct 2017 at 22:21

Steampunk said:
Lightning happens before the thunder. Sounds like you are getting a near strike and then hearing the thunder a few seconds later. You'd have to look at changes in your house or in the local supply to guess why a near strike is shutting off your power where it didn't before. It would help if you knew exactly why and where the power is shutting off - maybe an issue with a local substation?

I thought it might be some kind of safety thing for protecting your electrical stuff in your home,,,, no?

Steampunk · 28 Oct 2017 at 22:28

Phil2008 said:
I thought it might be some kind of safety thing for protecting your electrical stuff in your home,,,, no?

Nothing safe about shutting off the power to your house. It can damage electrics and electronics, corrupt and destroy data. What if you had some medical equipment that you needed to stay alive? How would anyone know that if they are just cutting power to your house?

EsaT · 29 Oct 2017 at 19:20

Steampunk said:
Nothing safe about shutting off the power to your house. It can damage electrics and electronics, corrupt and destroy data. What if you had some medical equipment that you needed to stay alive? How would anyone know that if they are just cutting power to your house?

Voltage dropping to zero for fraction of second from protection device shorting it to ground when voltage is enough to strike through air gap is heck lot better than all those electronics devices being fed surge caused by lightning.

And medical equipment should be able to tolerate black outs without going haywire and any really critical equipment should have battery or some back up power...
Or its designer would be most beneficial for mankind as lightning rod.

Phil2008 · 30 Oct 2017 at 15:25

DC stuff can deal with up and down voltage better then AC?

w1ze1 · 30 Oct 2017 at 15:27

So are you DC or AC or AC/DC?