UPS- using 12v 7ah batteries instead of 12v 9ah?

canidoit

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Will using lower amps batteries damage the UPS or equipment connected to it? If so, what sort of damage?


 

Johan

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no .it will just keep your equipment running for less time...the Ah rating tells you how many amp's you can pull if you want things running for 1 hour. if you pull 7 amp's and want it to last for 3 hours, you'll need a 21Ah batttery. if you only pull 1A, a 7 Ah battery will last 7 hours

J
 

canidoit

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Johan said:
no .it will just keep your equipment running for less time...the Ah rating tells you how many amp's you can pull if you want things running for 1 hour. if you pull 7 amp's and want it to last for 3 hours, you'll need a 21Ah batttery. if you only pull 1A, a 7 Ah battery will last 7 hours

J
Thanks John  :)

Would the circuit in a UPS unit prevent higher amps batteries to be used? It sais that the replacement batterries are 12v 9ah, so if I was to use a 12v 21ah, would it damage the UPS circuit?

Also what happens if your equipment connected to the UPS pulls 10amps and you only have 9ah batterries?

How does your answer work if the unit uses 4 batterries of 12v 7ah? Does the ah value increase by 4, eg 4 batteries in series becomes 12v 28ah?
 

trobbins

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The UPS will have a limited recharge current capability - which means it would take pro-rata (Ah:Ah) longer to charge the batteries if they were flat.  You will also need to add over-current protection if you extend the cables outside the UPS, and to isolate the batteries as they may be at hazardous AC voltage.  Unless the UPS specifically has an extension socket for connecting extra batteries (which some do), then I suggest you work through all the reasons why you want a different battery size, and try to find another workaround.
 

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