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I am having power cut problems in my country. I am using an uninterrupted power supply with these specs

  • waveform: modified sine wave
  • typical 15-20ms, 30ms max

My computer restarts when power goes down, the UPS does take over but while it does the computer restarts.

Earlier my router used to restart as well but I fixed it (I noticed the adapter of router had input 220-240 V , changed the adapter to 110-220V and now it does not restart)

My computer still restart Is there a solution for this ? thanks,

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migrated from Sep 13 '12 at 11:41

This question came from our site for contractors and serious DIYers.

Have you contacted the UPS manufacturers technical support? – Tester101 Sep 13 '12 at 11:40
What UPS are you using, and how old is it? What voltage are your power outlets? – cp2141 Sep 13 '12 at 11:48
It sounds like your UPS is capable of supplying enough power to your computer. – Ramhound Sep 13 '12 at 12:44
up vote 0 down vote accepted

Some power supplies don't like the large THD in pseudo-sine signals, although these are usually more expensive supplies (like the one mentioned in this article). These power supplies use an active power factor correction technology, and this part has problems coping with irregular voltage signals.

But you should contact both the UPS and power supply manufacturers and give them the details. Since the PC restarts (and then continues running on battery), it means that it is connected to the correct socket and that UPS presumably has enough power, so it boils down to large switchover time or THD.

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I'm guessing that you PSU isn't really good. Getting a good brand one (like seasonic), that should solve the problem.

It would be good if you specified the load of the computer and your current PSU.

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