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> [wta] UPS 650VA unable to supply power to PSU 650W, UPS PSU power

post Nov 30 2019, 10:33 AM

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QUOTE(adala @ Nov 26 2019, 10:25 PM)
APC BV650I  -- ThermalTake 650W 80PLUS GOLD

I have these.
When there was a power interruption, the UPS was not able to supply the power, and the PC power got cut off.

- No other devices connected to the UPS.
- Tested UPS with a monitor. Monitor still powered during power cut off.
- Energy meter reports 120W at maximum drawn by the PC.

Would 1000VA or 14000VA solve this?

Any advice?
Thank you.
Your ups is 375w vs cpu 650w.

Where enough supply?

Ups inverter only capable of of 375w.

Cpu + monitor is more than 650w.
post Dec 3 2019, 09:06 AM

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QUOTE(adala @ Dec 2 2019, 09:58 PM)
Thank you all for you feedback and advice.

Either I have to buy a higher power UPS or change my PSU to a lower power.

My PC is new together with the UPS. Bought in June.
user posted image
user posted image
The supplier didn't calculate and choose the UPS power output properly to suit the PSU.

When buy a UPS, 1st spec need to know is how much power need to backup your device.

Ex- PSU - 650W. Monitor - 120w. Total is 770w. Than add in some allowance for safety. 20-30%.

You need a UPS that can give 770Wx30% = 1000W.

It is not the battery in the UPS that give 1000W. But the inverter that converts DC12v to AC240V in the UPS is capable to run at 1000W.

So your UPS 650VA will shut down for safety if draws more than 375w. If not, the UPS will burn down.

2nd is the battery in the UPS. The battery gives the duration it can backup. The bigger the battery, the longer is can backup.

So to get a UPS, 2 spec need to check.

1) VA - the watt it can output
2) Time - Duration it can backup run at specific watt.


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