In article ,
The Natural Philosopher wrote:
Depending on the motor it takes about 200A to start a car for about 5
seconds.

If a reasonable charge current once started is 5 A that needs 200
seconds to replace the charge.

Or about 3 1/2 minutes.

These figures are well within an order of magnitude.

I have a very accurate voltmeter fitted to the old Rover. Alternator on
that is a slightly more modern unit with 100 amp output. Assuming the
battery is reasonably fresh to start with, the voltage, after a cold start
will have dropped back to the normal point after a drive to the shops. Say
a couple of miles of town driving.

--
*Cover me. I'm changing lanes.

Dave Plowman London SW
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