calculating ups batter backup

Initially when i first requested this myself, a friend kindly sent me towards the manual (a tale, clearly). Meanwhile, I discovered that calculating ups battery support isn't this type of large deal when i may have thought to begin with. To be able to make everything as obvious when i can, I'll make use of a small example. Let's assume the next ideas:
Inverter efficiency of UPS battery is 90% (standard is approximately 90% and 98%)
Battery finish point current 1.67 (usually specified around the UPS itself, or perhaps in its manual)
Environment temperature 77F
Presuming that we understand these things about our UPS : one string of batteries, 30 each, UPS rating 40kW and 6 cells per unit, we are able to break lower the information in three steps:
1.) Actual battery load for 40kW
40kW ?- 90% efficiency means a real 44.4kW load (you are able to calculate this by dividing the rating from the UPS by inverter efficiency ¡§C 40/.9 = 44.4kW)
2.) W per Battery
44.4kw (formerly calculated) is going to be divided by the amount of batteries we've available, and also the result will result in 1481 w per battery. (you are able to calculate this while using equation: 44.4Kw/30 = 1481W)
3.) W per each Cell
Giving the required data we'll subtract that every cell needs 247W. (calculate this while using equation: 1481W / 6 (the amount of cells per unit) = 247 w per each cell)
Now you can estimate the run-duration of your ups backup battery support system. Giving the truth that we all know that every batter has about 247W per each cell, and there exists a battery finish point current of just one.67V your run time ought to be approximately forty-five minutes and an hour.