Battery Bank Capacity Sizing

[enggines]

How would i solve the total capacity of a battery bank when rating of equipment being serve (Momentary, Continous & Essential loads) are not available. We have 6 battery bank(48 volts each) in different locations and we intend to have a centralized bank (in lieu of the 6-bank). Can I just add all the Ampere-Hour rating of the existing battery bank with the sum be the basis of required capacity? Say, bank1=75AH, 133minutes reserve capacity, + bank2=160AH, 300minutes, + bank3=82AH, 155minutes, so on...with the total AH as required capacity OR get the highest rated Bank say 160 AH, 300 minutes reserve capacity plus additional factor (say 1.5) is sufficient. Any comment, suggestion or the proper method would be highly appreciated. Thank you.

 

[DanDel]

I would be more comfortable looking at the loads, but if can't get them, and you are having no problems with the battery bank loading now, you will probably have a conservatively sized bank if you sum the existing Ah values.
I would definitely look at the distances and cable sizing involved from your new bank to the existing loads, however; voltage drop could be of concern.

 

[busbar]

Of potential applicability:

IEEE 485-1997 Recommended Practice for Sizing Lead-Acid Batteries for Stationary Applications

IEEE 1115-1992 Recommended Practice for Sizing Nickel-Cadmium Batteries for Stationary Applications

IEEE 1184-1994 Guide for the Selection and Sizing of Batteries for Uninterruptible Power Systems

IEEE 1189-1996 Guide for Selection of Valve-Regulated Lead-Acid Batteries for Stationary Applications