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Old 08-22-2010, 01:37 PM
Rob Pruijt Rob Pruijt is offline
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Join Date: Dec 1999
Location: Utrecht, the Netherlands
Posts: 418
Quote:
Originally Posted by gidpor View Post
For me the battery issue has been resolved, but could you please explain more about using a headlight lamp. I've not heard of this before
If the resistance of the battery is close to zero, the lamp gets 12V, with a 60watt lamp, the current will be 5 amps.
When the battery has more charge the resistance will rise, the lamp will get a lower voltage, but there will still be enough current to charge the battery in a controlled way.

If you connect a fully charged battery directly to a completely drained one, the current can be very high (several hundreds amps).

Of course you can't jump start a car through a headlight lamp, just slowly charge it until it reaches a safe voltage.

It is an old trick, from before the electronically controlled chargers.

Rob
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