Power Bank Needs

[Clare]

I'm looking to add a Power Bank to my new build. I don't know how to find out how much watts I need to keep it running more than 30 seconds. How do I find out how much power I need and how long I'll have.

[tarfeef101]

If you're talking about a UPS (uninterruptible power supply), then you want to take a look at a few things:
1) They come with a maximum power draw over which an internal breaker will flip. So, even if it is rated at say, 1500VA, if the max draw is 100W, that's not enough to power a gaming PC under load. So ensure it has enough power draw available to you on battery.
2) The aforementioned VA rating. Generally, you want it to exceed your power draw in watts by say, 1.5x (debatable). So, for my home server, which is about 200W maximum, I have a 650VA unit with a max power draw of 450W.

[Clare]

2 minutes ago, tarfeef101 said:

If you're talking about a UPS (uninterruptible power supply), then you want to take a look at a few things:
1) They come with a maximum power draw over which an internal breaker will flip. So, even if it is rated at say, 1500VA, if the max draw is 100W, that's not enough to power a gaming PC under load. So ensure it has enough power draw available to you on battery.
2) The aforementioned VA rating. Generally, you want it to exceed your power draw in watts by say, 1.5x (debatable). So, for my home server, which is about 200W maximum, I have a 650VA unit with a max power draw of 450W.

So if I have a 850 watt power supply does that mean I need a 1700 watt UPS

[tarfeef101]

1 minute ago, Clare said:

So if I have a 850 watt power supply does that mean I need a 1700 watt UPS

No. That's a rather "intense" UPS. 

I can buy a 1600W power supply to run a pentium CPU and no GPU. That system will draw like, 100W under load. What you need to do is figure out how much power your system draws under load. Which is almost never the same as your PSU's rated maximum wattage. You can get close to that number by adding the TDP of your CPU and GPU(s), and maybe 50-100W extra for "everything else". If you overclock, then more, etc. But hopefully you understand a bit more about power draw once you start doing things like that. 

Once you have that number, again, make sure the PSU is rated to supply that much wattage under battery operation. Then, pick a VA rating around 1.5x the power draw you came up with for your system. 

Oh yeah there are some sites like https://seasonic.com/wattage-calculator that can help calculate your computer's power draw if you're unsure. They aren't perfect, but are probably a good start

[Clare]

1 minute ago, James Evens said:

APC has a nice calculator.

You select what you have (you must know you pc wattage) and they say what ups of there lineup fits your need. For sanity check make double you wattage and you have your VA rating (just a rough approximation). Oh and make sure you get a true sine wave and not a cheap "pwm" ups.

Other things to consider is the type of ups (online, line interactive, offline).

online, line interactive, offline?

[Clare]

1 minute ago, James Evens said:

The way they work. 

offline: the cheapest, only protects against outages

line interactive: "regulating" the output also during normal operation (what you probably will chose in the end)

online: separating the input from the output (AC input -> DC -> battery (DC) -> AC output) which offers the best protection

 

All types have benefits and problems for the online UPS it is beside cost the efficiency during normal operation.

I might go with one of these: 

https://www.amazon.com/CyberPower-CP1500AVRLCD-Intelligent-Outlets-Mini-Tower/dp/B000FBK3QK/ref=sr_1_3?ie=UTF8&qid=1543769398&sr=8-3&keywords=Uninterruptible+Power+Supply

 

https://www.amazon.com/APC-Battery-Protector-BackUPS-BX1500M/dp/B06VY6FXMM/ref=sr_1_6?ie=UTF8&qid=1543769398&sr=8-6&keywords=Uninterruptible+Power+Supply