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Charging times

Posted: Tue Sep 11, 2007 9:08 pm
by floydster
Hi folks,

Am I correct with this calculation?

I'm trying to figure out how long it takes to recharge a battery.

If I have a 12 volt 110Ah battery and have had a 1 amp device on for one hour then I need to replace that one amp. Using a 20w source to recharge the battery I figure that

20w/12v=1.7A so replacing the 1A used in an hour would take 0.6 hours in ideal conditions.

Please be gentle, I'm not very good at this stuff

Floydster

Posted: Wed Sep 12, 2007 5:52 pm
by arsharpe
Sounds good.

These sort of ideal conditions dont actually exist in the real world.

You really need to take account of the losses in discharge and charge as well. Which means that you probably need to increase the charge time by about 30% to 50% (depending on your battery type) to be realistic.

So 0.6 hrs becomes something like 0.6 x 1.3 = 0.8 hrs

Also, I assume the 20w source has a 12v output and depending on battery type needs to be supplied by different types of charger.

Well done anyway.

Rob

Posted: Wed Sep 12, 2007 8:45 pm
by floydster
arsharpe wrote:Also, I assume the 20w source has a 12v output and depending on battery type needs to be supplied by different types of charger.
Rob


Thanks. The source is 12v too. Didn't realise the loss would be just as much though.

Thanks again,

Floydster