Some questions on battery backup load and how it's calculated when the UPS is turned on

[mapc_apc]

Can anyone please explain how maximum load on battery backup is calculated?

Let's use BACK-UPS ES - BE850G2-UK UPS as an example, it's 520W to which I want to connect an OLED TV(150W), a PS4 Pro(310 W) console and a PS3 slim console(110 W) for a total of 570W, more than the device can support.

If I do go ahead with this setup, will the UPS beep due to overload as soon as I turn it on or it will only complain the moment all three devices are switched on and using maximum power?

For example, if the TV is on (150W), the PS4 Pro is on(using its full power 310 W) but the PS3 console is turned off(1W), meaning that I am technically using 460W out of the possible 520W, will the UPS complain? And if it does, will it simply shut down or will I have a couple of minutes time to properly turn off my devices before turning the UPS shuts down?

And finally, why is PowerChute showing that it's not recommended to connect more devices to the battery backup in this video? https://youtu.be/n9omkITPn28?t=101

According to the screen it seems that this user is using 350W out of a possible 540W so why the warning?

Thank you.

[BillP · Accepted solution]

1) It will only complain once it goes past it's maximum power output or gets very close to it.

2) I can't say for certain what will happened when the UPS is on mains different units behave different ways but on battery the UPS will turn itself off straight away if it is overloaded by that much.

3) There is lots of reasons why it is recommending not to add any more devices some might be:

1. Peak power
   • A PC with a 450 watt power supply might only use 50 watts on the desktop but 200 watts playing video
2. Time on battery
   • A UPS that only lasts 30 seconds might be useless, pushing it to it's limit will mean that the battery will have a very short run time.
   • For the unit above the run-time looks like this: 
     050w: 79 mins
     100w: 35 min
     200w: 13 min
     300w: 7~ min
     400w: 3.5 min

-Gavan

[mapc_apc]

Hi Gavan.

Thanks for the reply, very helpful!

So if I understood correctly, if I make sure to keep the PS3 turned off when using the PS4 Pro and if the PS4 Pro as well as the TV are using their peak power, I should be safe as I'm using 460W out of the possible 520W.

Alternatively, I could play it safe by opting for a bigger UPS even though in my specific case I would prefer to stick to two BACK-UPS ES because they are not IEC C14.

In that case, having made my calculations with additional devices connected to the two UPS, can you please help me understand the battery runtime for these two units since the runtime charts on the APC website are only for the Smart products:

Backup ES 850VA
Load: 404W (out of a possible 520W)

I know it's 6 minutes for 350W(using https://www.amazon.co.uk/dp/B0828G42KN) so with 404W we're looking at maybe 3 minutes?

Backup ES 700VA
Load: 260W (out of a possible 405W)

Maybe here we're looking at 6 minutes?

[BillP]

The numbers above are for the 850, as for the 700 it's:

050w - 43.5 mins

100w - 21.5 mins

200w - 08.5 mins

300w - 03.6 mins

I can't give you more precise details that not how we publish the run-times.

https://www.apc.com/products/runtime_for_extendedruntime.cfm

-Gavan

[mapc_apc]

Thank you Gavan, very much appreciated.