Question Advice needed on UPS purchase

[Drone4four]

Greetings!

My new home and local neighborhood has been expericing brown outs every few weeks. The power for my whole home will flicker off /on for a few seconds. It's not a big deal but the fleetingly temporary brown out is enough to power cycle my Linux PC and interrupt my workflow So in the interests of best practices I figure getting a battery-surge protector combo would be a good investment.

• Here is my PSU model: GIGABYTE GP-P650B "650 Watts" 80 PLUS Bronze Certified Power Supply (GP-P650B)
• I have an LG "38WK95C-W" monitor ("60 Watts") . Full specs: https://www.lg.com/ca_en/monitors/ultrawide/38wk95c-w/
• Not sure about my modem

I believe those are the only 3 electrical devices that require protection.

I am considering these two Uninterruptable Power Supply Systems:

• CyberPower CP1500AVRLCD3 Intelligent LCD UPS System, 1500VA/900W, 12 Outlets, 2 USB Ports, AVR, Mini Tower, Black
• Amazon Basics Line-Interactive UPS 1500VA 900 Watt Surge Protector Battery Power Backup, 10 Outlets - Black

Here are my questions:

1. They are both 900 Watts. That is greater than my power requirements. But the only other options I could see on Amazon were 600 Watts which is less than my PC PSU.
2. What does "1500VA" mean? That seems to be an important characteristic of these UPS Systems and I am not sure where my hardware fits in with this requirement
3. The first one says it should last "8 hours" which leads me to think this is wayyyy overkill becasue my power goes out for just a few seconds. I don't need a battery to last for hours.
4. What other factors would you people suggest I consider?

 

[Drone4four]

To correct myself, there is a chart comparing different UPS characteristics. It says charge = 8 hours. But "Run Time" ranges from 10-12 minutes. Is that really how long to expect the full charge to last?

 

[Corwin65]

UPS is there to allow you to save and power down.

 

[geofelt]

Go to the apc web site.
They will have a calculator app to size a ups.

 

[Ralston18]

And, as I understand the working environment, UPS or not be sure to have a good backup routine in place.

 

[slurmsmckenzie]

In case it is a helpful example I'm using an APC Back-UPS RS 900MI which is 900VA / 540W and I have the following plugged into it:

Desktop PC with Ryzen 5950X & 4070 Ti (1000W PSU)
LG OLED monitor
Netgear Readynas 202
Zyxel 2.5gb network switch

When I'm just browsing my APC tells me I am using 140W of power and if power was lost it would last approximately 24 mins - as others have said this is pretty much just time to shut everything off cleanly. Of course if there was a momentary brown-out then it would cope with that just fine.

Just fired up Forza Horizon 4 and during game play my usage went up to 240W and it indicated 13 minutes of time if the power was lost. Even though I have a 1000W PSU (which is way OTT I admit) my 540W UPS does me fine. From my perspective your UPS does not need to exceed the W rating of your PC PSU.

Obviously the amount of power that you'll be drawing at any one time depends on your system and what you're doing, if there was a way to figure that out it would help. As well as the APC software I've also used HWINFO in the past - I used to have a USB link to my PSU which made it really simple.

The only other thing I'd add is that some people say that you should have a pure sine-wave capable UPS, I don't and have never noticed an issue but YMMV!

 

[Eximo]

If you want longer term power for outages, that is a different question at much greater expense.

And yes, batteries in UPS are slowly charged, so they can't handle outages in rapid succession.

If you are comfortable with electronics, lead acid UPS can be easily modified to use larger external batteries, of course those can be quite expensive.

Another cheap way to get larger amounts of stored power is to buy old data center/rack UPS and do the same thing.

 

[Paperdoc]

The "1500 VA" spec is important to electricians, but for regular users the WATTS spec is more useful. These units have ratings of 900 W. That is the MAX power rate they can deliver when your mains supply fails.

Now, the real thing to watch is for HOW LONG? For the Cyberpower unit its website claims it can deliver power at HALF that rate (450 W) for up to 12 minutes, and at FULL 900 W rate for up to THREE minutes. That's all you can get from units like this. This underscores the statement that the correct way to use such a device is to act immediately to stop all use and shut down your system in an orderly fashion BEFORE the backup power fails! Of course, this presumes that someone WILL be right there to recognize the main power failure and take these shut-down actions right away. If the system is running unattended, shut-down is unlikely to be done in time!

OP, you state you are concerned with short-term sags of power you call Brownouts. So IF you can be sure you (or someone else suitably prepared) will always be there when power sags AND you are confident that the interruption WILL be brief, you can delay your shut-down process for a few minutes and hope the interruption really IS short. During that time this UPS will keep your system running smoothly. If it takes too long (3 min? 10 min?) you MUST proceed with smooth shut-down. Do not ever depend on having your system keep running for a long time.

We have a couple of UPS units in our home network system. Each powers only a couple of small devices like routers that draw less than 50W, so their runtime on power system failure is hours. The entire network is not working (servers, etc.), but WiFi (via the routers} is available to battery-powered laptops, phones and tablets.