I want to power a small credit card terminal rated at 24 VDC 1.5A. I assume the 1.5A is with the built in thermal printer running and not continuous. I need to run the terminal maybe 4 hours a day and will power it down when not needed and will recharge overnight. I have seen a few charger units for 12V Sealed Lead Acid (about 8 Ahr) which would require running the batteries in series and a NiMH charger that would work with a 20-cell pack (series) rated at 2-3.5 amps. Anyone have a better way to go with this? The cheap way out would the the car 12V charger I already have, a couple of small alarm sized Sealed Lead Acids, a switch, fuse and a box. Got anything more sexy? I would not sneeze at "off the shelf".

 

There are 12V-24V DC-DC Converters under $100 that would supply 24V/3A Max from a 12AH, 12V battery of any type, but I'm thinking about a deep cycle car battery for the source, it's a little heavy though.

How much will this need to be moved around?

 

It would be an art show environment. Dolly in one day, dolly out the next. Static for the rest. I've seen plenty of car bats at the shows with inverters, but if the credit card machine will run on 24 VDC, why invert? I will look at the converter, thanks.