I want to run a 120 volt 6 amp pump for 24 hours on dc power what do I need for batteries?

Question

Would like to run this on ac sometimes then a dc to ac inverter other times

Answer 1

So a 100% efficient inverter powered by a bank of 24v batteries  would be drawing 30 amps continuously.

There are setups like that in places like server rooms.  I've seen the one at the company where I work.  Looks like about 50 car batteries wired together.

Most sealed lead-acid batteries are rated in amp-hours for 20 hour time periods.  For example, this computer battery backup battery pack is 24 volts, rated at 17 amp-hours when it takes 20 hours to discharge: http://www.batteries.com/productprofile....

So that means 20 of these battery packs in parallel with each other will provide 17 amps for 20 hours.  To get 30 amps for 24 hours, I'll do some algebra.

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43 battery packs rated at 17 amp-hours, 24 volts, will provide 30 amps for 24.4 hours.  At a cost of $92.43, that is $3,974.49 for the cost of the batteries alone, not even including shipping or the cost of a large expensive inverter.  You may be able to do it cheaper with car batteries, but they aren't rated in amp-hours so you don't know if they will last long enough.

Answer 2

I suggest that you contact a battery professional. There's this online battery store that I always go to, they have batteries for all applications and they're very helpful and friendly. Here is the link:

http://www.batterytex.com

Answer 3

P = VI

Power = Volt * Current

Power = 120 * 6

Power = 720 WATT.

There no way you can get enough batteries to run this device on battery for 24 hours. Even if you got a car battery, it will only run at 720 watt (using and big inverter) for few minutes.

Assuming that you are using a car battery (12v), then you would need to draw 60 AMP for 24 hours (assuming 100% effeciency).  That's crazy.

Good Luck...

Answer 4

Holy c**p that would be A L O T of batteries!!!

First you need to know how much current the inverter will require to produce 6A at 120V.

Crude calculations tells me that your going to need over 24 automotive-style batteries. Remember, the inverter will shut down on a low input voltage so you need to keep it above 11.8V (or somewhere around that).