Saturday, August 19, 2006

What's the Difference Between UPS Battery Voltage and Amperage?

Question: What is the difference between voltage and amperage in relation to replacement UPS batteries?

Answer: When replacing a battery in a APC UPS also known as RBC pack, we must always maintain the same voltage that we started with. The voltage of the battery is the push, or pressure, as one would relate to the pressure in a water hose. Amperage, on the other hand, is the amount of energy use as measured in amp hours, similar to the amount of flow in a water hose. So, to summarize, we must always use the same voltage in our replacement batteries, but we can change the amperage slightly to increase our run time. If this is done in small amounts, the effect on longevity of the APC UPS unit will not be adversely compromised.

16 comments:

David C. said...

Hi, Great information. I have several extra 12v AGM batteries ranging from 4 to 12 amps. My UPS has a 12v 7amp AGM battery. Can I use any of these extra batteries in the UPS? My primary goal is to charge these and use them in other applications, not for UPS backup power.

Sincerely,
David

APC UPS Battery Expert said...

David, Your system is designed for an set amperage, going to larger battery will increase the backup time but can overtax the unit ability to recharge the battery. I feel if you stay within 15% of the original spec. you'll be safe. Hope that helps.

Anonymous said...

So you would say that a 7A replacement battery in a 5A system would be too much for it?

APC UPS Battery Expert said...

The difference between volts and amps is a kin to a water hose: the pressure is the volts and the amount of flow is the amps. You can put in a slightly larger amp battery and it will give it a longer run time, but if the amperage is too large you will overwork the unit -- go ahead with your 7.5 amp battery if it will fit.

Anonymous said...

can i use a 12v battery in my ups which is generally used in trucks or with inverters

APC UPS Battery Expert said...

NO, UPS units can not fully charge a battery of that amp hour.

Anonymous said...

CAN WE BUY INVERTER BATTERIES INSTEAD OF UPS BATTERIES FORCHARGING UPS ,KEEPING THE AH & VOLTAGE SAME..IE 100 AH & 12 VOLTS

Gary O said...

I am looking at buying an APC RP 35 replacement battery to sue for a special project. what is the voltage and amp rating?

APC UPS Battery Expert said...

Gary O

12 volts 3.5amps @ the 20hour rate

power supply said...

Amperage is the amount of electrical energy flowing through an appliance at any given time.

UPS batteries said...

Hi, Great post. Wonderful write up.

mikibabs said...

is it ok to use a 6 volt 10Ah battery on my APC UPS if the original battery was a 12 volt 7.5Ah?

APC UPS Battery Expert said...

MikiBabs,

No, you must match volts and physical size

APC UPS Battery Expert said...

To: INVERTER BATTERIES INSTEAD

NO.
The switch over too slow.

It would shut unit off.

Anonymous said...

I have 650 VA APC UPS. I have only option available here is 7.2 Amps. But I want to go for higher. I have other option available which has to use as external battery is 12V 12 Amps and 12V 17AH. I want to go with 17 AH but I want to know the disadvantage if using such higher capacity. I want longer backup time.
Regards,
Manoj

APC UPS Battery Expert said...

Think of voltage and amps as the pressure and flow of a garden hose, the volts is the pressure and amps is amount of gallons that flows, both are preset by the needs of the UPS, The voltage must be the same, but amps need to meet or exceed the manufactures specs.