Charging a battery

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Fri 19 Nov 2004 16:16
Charging a battery - Cambridge
Flat battery on my Herald...
I realise this is basic, but how long should I leave my battery on charge?
It is a 40ah battery and the charger on low setting reads 3 amps. Does this mean I should leave it on for 13 hours?

Thanks for your help.
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Fri 19 Nov 2004 21:06
Charging a battery - CG
Something like that, depends on the level of charge remaining. Is your charger the 'automatic' type where the charge is reduced as the battery voltage increases? That way, you can leave it on for long periods to just trickle. Problem with a fixed rate charger (even 3A) is that you can overcharge the battery and damage it if you forget to switch off.
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Sat 20 Nov 2004 11:33
Charging a battery - John24
Depends on usage. Best way in my experience is to charge for a couple of hours, which should be enough to get the car started, then normal usage, if your electrical system is working correctly, will charge battery to its optimum.
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Sat 20 Nov 2004 11:34
Charging a battery - John24
Sorry. Should have added - depends on reason battery is flat, in the first place.
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