UPS Battery Life under Load

Hi,

I have been trying to figure out exactly how long my 120Vac input, 1440VA(865W), 120Vac output, UPS will last under load during a power outage.

It's APC's J Type Power Conditioner and Battery Backup J25B. Listing is https://www.amazon.com/APC-J25B-8-Outlet-Conditioner-Battery/dp/B003GSLL2E

Amazon give it's prediction but I wanted to calculate it out.

I know that I'm plugging to it a 120Vac load that draws at max 1amp.

so...VA = V X I
= 120V X 1A
= 120



How do I incorporate time? There has got to be another spec. variable I am missing?

Any help would be great.

Thanks

Going to the maker's web site got me this:

https://www.apc.com/products/runtimegraph/runtime_graph.cfm?base_sku=J25B&chartSize=large

If that link gives trouble, here it is:

Thanks. I did have trouble viewing it. Very glitchy page.

Looks like I'm looking at about just under 1 hour for max load. I suppose that's not too bad.

I'm curious if anyone has any insight as to how one would normally calculate this for yourself? Perhaps, there just isn't enough info? If so what am I missing that the manufacturer isn't providing. Granted they provide the graph which is very helpful but I'd just like to know for my own knowledge.

Thanks again for the reply Mike.

wuchy143 said:

Looks like I'm looking at about just under 1 hour for max load. I suppose that's not too bad.

Click to expand...

Uhh...

I see about 70 minutes at under 100 watts load and less than 4 minutes at max load on that chart.

ah you're right! I read the graph wrong. didn't realize the scaling. so for 120watts it's a runtime of about 50 minutes.