Answer / shailesh singh

Battey backup(va)=mah×v×n of battery/watt

Answer / sathiyanarayanan

backup formula= KVA/DC LOW *POWER FACTOR

FOR EX:2 KVA/120 DC VOLT(SYSTEM VOLT)OUR MAINTAINED POWER

FACTOR (0.8 P.F),PER BATTERY=12V(DC LOW=10.8),HERE USING THE

SYSTEM VOLT=120V SO,10 BATTERIES-10*12=120V


DERIVATION : 2000/108*0.8

AH=14.81(APP.17 AH BATTERY) given 30 minutes backup

Answer / chetan singh

Battery Volt X No of Battery X Battery AH / Load in watt

Answer / srini

what is 130

Answer / mehboob

( Battery Voltage * AH Rating * Efficiency) / VA Rating =  X
X * 60 = Estimated Run Time in Minutes




So let’s pretend we’re looking at a theoretical UPS unit that has the following specs:




VA Rating: 700
Battery Voltage: 12
AH: 9
Efficiency: 0.9 (90%)




When we plug those numbers into the equation we get the following:




( 12 * 9 * 0.9 ) / 700 = 0.139
0.139 * 60 = 8.3 minutes

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