UPS/Inverter recommendation for 750-850W PC

E

enthusiast29

Juggernaut
Hi,

I have a PC with 750W PSU and dual monitor setup.
Currently I'm providing it power through my inverter which is 900VA (756W max) sine wave, you know where I'm heading with this...

So obviously when I run something heavy and power cuts, the inverter shows heavy load and trips the whole circuit for the house.
On idle/light loads it's fine but since this is my personal use + gaming machine I don't want it to have an unsafe shutdown.

Please suggest ideal UPS for this so that I can at least close my game and put the system to sleep mode (or power off) until power is back.

OR​

Should I upgrade the inverter capacity to a higher model such as 1500-1650VA? My doubt is will it be able to switch fast enough when my PC is on load?

EDIT: TL;DR, my solution is here. This is for me personally, others may like some other approach.
 
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So there's an update on this situation...
I've been testing this weekend and I brought home another inverter from a relative who had a spare + battery (hardly used as per them).
Unfortunately they had a square wave invertor so I didn't want to risk it on my PC.

Instead I disconnected my main home inverter which is sine wave and used that on the "new" battery. This time I dragged that inverter in my room and only connected my PC to the output (no other home appliance load).
Waited to fully charge that "new" battery and put the system on full load and simulated a power cut scenario. Bam! The PC shut off...

Now I waited for the inverter to reset itself and didn't connect mains, cold started my PC again (this time only on battery backup, no mains). Ran a stress test again and surprisingly no issues in sustaining the load while the inverter is already switched on battery. So this means even if I have an inverter dedicated to PC it won't do me any good because the issue is with the switch-over time being too high (15-20ms advertised).

I had my mind made-up a day before to buy a separate inverter for PC but had a hunch to test first and it helped saving money there.

Now I'm thinking to buy APC 1100VA UPS. My plan is to have it connected to some inverter connected socket and only my PSU connected to the UPS. On full load 3070 + 12400F config should only pull about 400-450W max from the wall.
Monitors will still be connected to the inverter.

Will this help? Does anyone on this forum not deal with power issues with their gaming/productivity machines? Need some opinions/recommendations on this.
 
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My i5 12400 + 3070 rig with 2 monitors (25W + 15W) consume 400-420W while gaming. I measured it. I'm using APC BX1100 UPS.

BTW UPS mode exists on certain inverters. A friend of mine used his gaming PC (3700X + 2070S) on his inverter with home load connected. Initially, his inverter also didn't take the PC load while gaming & tripped whenever a power cut happened. Then he found out about UPS mode, which solved his issue, was a switch on his inverter. I think he has a 1.5 kVA inverter. I don't think battery capacity matters much on load, just how long it will run. Usually most have 150Ah batteries.
 
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@OMEGA44-XT Thanks for the reply and sharing your experience man.

I have the UPS mode on the inverter and checked using that too, same result. Guess my inverter's switchover time (advertised as < 20ms) is too high.
I checked my PSU's holdup time and it's >16ms. So maybe I'm missing by a couple milliseconds only.
I'm thinking to only plug-in the PSU to the UPS and nothing else to save on power budget. I was just looking to confirm that BX1100 is enough for a switch.

If you can confirm me that it's able to switch in time for a stress load as well that would be awesome!
You can run any system stability test which stresses CPU and GPU together (AIDA64?) and then simulate a power cut. If the UPS is able to make the switch in time and PC doesn't shut off then it'll make my day... Oh and don't forget to mention your PSU as well.
 
My BX1100 easily handles gaming load. I get under 10 minutes of gaming time, maybe 5-6 mins now sadly after 1.5 years. It used to run my PC for web browsing for close to 30mins when it was new, now its barely 15mins or so. For web browsing, I measured the load at 160-200W.
 
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OMEGA44-XT said:
https://www.tomshardware.com/reviews/nzxt-c750-power-supply-review
This says 17ms+
Click to expand...
Thanks, I couldn't find it as well IDK perhaps they measured it?
Anyways just wanted to compare with mine. I have Deepcool DQ750M-V2L and that advertises a hold-up time of 16ms+ in specs. So a switchover time from any UPS which is faster than this should be good as long as the load is under capacity.

BTW if anyone's aware of an inverter which has a switchover time of upto 12ms can please suggest a brand/model?
 
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enthusiast29 said:
Should I upgrade the inverter capacity to a higher model such as 1500-1650VA? My doubt is will it be able to switch fast enough when my PC is on load?
Click to expand...
This is best course of action I can recommend as I'm also using a similar setup(not PC, but a whole office/entertainment room) load is more than what a eco volt 1050 (900w capacity) could handle. So I got 1400 watt capacity eco volt 1650. It easily switches quick enough for my 65 inch oled, PS5, 200 watt speakers, and 2 laptops, 2 27 inch screen and another set of 200 watt speakers.

Here's a dedicated thread for it:
Post in thread 'Inverter installation: is it possible to install inverter for a single room in the house?' https://techenclave.com/threads/inv...-single-room-in-the-house.214186/post-2463234
 
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@vishalrao Bro don't go for Luminous there's no guarantee it'll work for your PCs if on load.
If you have an option to test first, do that instead.

I'm personally using Luminous Eco volt Neo 1050. I tried only the PC on full load and it didn't keep it up when switching. Only usage was around 450W (12400F + 3070). It runs fine after the switch even on load but what's the point if it can't survive on switching...

There's this inverter from Su-vastika: https://www.jiomart.com/p/homeimpro...e-office-pack-of-1-1600va-1280w-12v/604008133
They advertise under 10ms switching time but IDK how true it is... It is government recognized: https://suvastika.com/

nitin_g3 said:
It easily switches quick enough for my 65 inch oled, PS5, 200 watt speakers, and 2 laptops, 2 27 inch screen and another set of 200 watt speakers.
Click to expand...
I get that and it seems alright to me. You don't seem to have desktop machines which draw a lot of power and current on load. All of your other devices have either a power brick (in case of laptops etc.) or don't draw too much power so their inbult capacitors can hold up when switching.

I'm all in favor of getting an inverter instead of UPS but if and only if your device survives the switching time.

I have a question, did you try to use everything on the older less capacity inverter when not connected to mains? This is to check if it can handle the load or not.
As I said my inverter can handle my PC on load when on battery it's just when it goes from mains -> battery and PC is on load my PC can't hold long enough so that the switch is complete...
 
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enthusiast29 said:
I have a question, did you try to use everything on the older less capacity inverter when not connected to mains? This is to check if it can handle the load or not.
Click to expand...
Yes, My first inverter setup was neo eco volt 1050 and a single 200 ah TT battery.
I kept my OLED on full brightness with a bright scene and GoW Ragnarök running to test it. And 1050 couldn't take it and went down with a beep. That's why I went with a 1400 watt capacity neo eco 1650 with 2 TT batteries which handled that instant heavy load after a power cut pretty well. I always run inverter in UPS mode.

If you still doubt that a higher load capacity inverter won't be able to handle your PC then I recommend a UPS with your PC to keep it running while switchover happens. I have my office equipments (laptops, speakers and monitor, router, pi) still connected to my APC 1100va ups.

I would recommend this approach:
  1. Get a higher load capacity inverter and another battery if you just have a single yet. Keep it in UPS mode.
  2. Test your system with full load for switchover.
  3. If it takes load well then good else get a UPS also and connect your tower only to the ups.
 
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nitin_g3 said:
I would recommend this approach:
  1. Get a higher load capacity inverter and another battery if you just have a single yet. Keep it in UPS mode.
  2. Test your system with full load for switchover.
  3. If it takes load well then good else get a UPS also and connect your tower only to the ups.
Click to expand...
Thanks for the suggestion, this is inclined with my thoughts as well but the only thing that bothers me is if the new inverter doesn't do me any good it's money wasted. Dealers here won't take it back.
My other home electrical load is enough for the Eco Volt Neo 1050 which I already have. That's why I'm thinking for approach 3 and I'll plug the UPS on inverter after switch happens just in-case if it trips while it was plugged in before the switch.

Also we seem to get peak 260-270V input here (since a month) so the Luminous inverters (the two models I tried) both intermittently don't detect mains power and switch to battery a lot, majority of the time. Although I have done all testing in UPS mode but it didn't matter.
 
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enthusiast29 said:
Also we seem to get peak 260-270V input here (since a month) so the Luminous inverters (the two models I tried) both intermittently don't detect mains power and switch to battery a lot, majority of the time. Although I have done all testing in UPS mode but it didn't matter.
Click to expand...
This is really an issue, I'm not sure if there are voltage regulators which can work continuously for such scenarios.
 
What 'UPS mode' actually is varies between manufacturers. For a few, it's quicker switching time. For most others, it's switching to battery on smaller voltage fluctuations — like at 185v instead of 140v (example). Some manufacturers call this "regulated/unregulated mode."

I've had four inverters over the years, they're all not very well suited for computers at load — they just don't switch fast enough. I still use them, but I oversize my power supply by a lot (most for efficiency reasons — if the computer pulls 400w at load, I use a +800W power supply) and this is usually enough to mitigate the slower switching times. It doesn't always work though.

For voltage fluctuations, mainline stabilizers can be used. This adds cost though. For smaller single point setups like a gaming pc, a UPS makes more sense than an inverter since it'll handle voltage fluctuations and have fast switching and you wouldn't need to upgrade your power supply. The downside is that the runtime would be significantly shorter than with an inverter.

You could connect a UPS to a secondhand inverter and battery and get the best of both worlds and still be in a reasonably cost effective price range.

enthusiast29 said:
Su-vastika
Click to expand...

Fun fact: Their blog/articles link back to TE discussion threads as references.
 
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1) Buying a new UPS for your PSU and keeping the monitor plugged into existing inverter is the sensible way.
2) If you want to buy a new higher capacity inverter then make sure you account for any new devices you'd be adding to your inverter backup in near future.

I use some pretty old 3KVA Luminous inverter. Most of the times it switches pretty fast on inverter mode to not affect the PC. But the UPS mode works flawlessly.
 
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I have online UPS inverter! works like charm. no pc shutdown at all even when ac is on and power is gone :P I have Luminous 4KVA
 
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