In article ,
charles wrote:
In article , Dave Plowman (News)
wrote:
In article , Huge
wrote:
P.S. re-reading your posting, the reason people suggest
disconnecting the battery is that most modern cars have a
substantial current drain even when switched off (I've measured it
at several hundred milliamperes). This will rapidly flatten and then
ruin a car battery. Which is why I use a float/trickle charger
(sometimes called a "battery conditioner").

If you take a fairly normal (large) 75 amp hour battery, a drain of 1
amp would flatten it in 3 days. Pro rata for a lower current. And it
would fail to start before the battery was totally flat.

Most cars can last about 3 weeks without being run. Which would
suggest a quiescent current draw of rather under 100mA. But it may be
higher until the electrics finally go to sleep.

The main source of current drain is probably the radio. When you switch
it off, you're only turning off the amplifier, the tuning bits, etc, are
still powered. Alarms also take a bit of power.

On a modern car you might be amazed how much is powered up all the time.
My radio retains its station memory etc even if totally powered down.

--
*I couldn't repair your brakes, so I made your horn louder *

Dave Plowman London SW
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