Digital picture frame question

[markymark2406]

i have a digital picture frame which says it has to be supplied with 12volts 0.8amp supply which I have I would like to power it by a battery as I'm going to be using it a art show on my stall,I have a 12volt batttery which is saying 7.2a/h will this do?

 

[Lucid]

Yeah, it should be.

Matching the voltage accurately is fairly important. The current though is a bit like the size of a petrol tank. The bigger the AH rating then the bigger the capacity. Batteries have internal resistance so there'll be a bit of power lost due to that, but if the battery is in good condition and fully charged then you might be able to get 8 hrs worth of display time from the photo frame, and possbly more if the 0.8 amp rating is the maximum current draw rather than a lower figure for constant delivery.

 

[big-all]

as an aside a fully charged battery can be as high as 20% overvoltage or 14.4v so may or may not be a problem
also as the battery runs down the voltage can drop below 10v

 

[markymark2406]

Ok I have connected a 12volt 7.2 amp battery and it works fine, now to charge what voltage and amps would I need ??

 

[motorbiking]

standard car battery charger will do it.

 

[markymark2406]

What Volts Amps if I have a desk variable power supply 13.5v?

 

[Sam Gangee]

It depends. What type of battery is it?