"Lem" wrote in message ...
Will an automatic car battery charger trip out at the correct point
if the battery is left connected to the car?

I don't want my charger to keep pumping current into my battery if it
is fully charged in case my battery suffers some sort of damage!

Thank you for any views.

Lem

-------------------

BACKGROUND ...

A thread last September in the uk.rec.cars groups called "Need to
disconnect battery before charging?" http://snipurl.com/chww seemed
to generally conclude that it is alright to charge a car battery
without disconnecting it first.

My battery charger is rated, by the manufacturer, at 11 Amps. It is
probably not 11 Amps but it is bigger than I need for my old
Mazda 1400cc car. It cuts out automatically when the battery is
charged and the cutout has an selector for sealed batteries and non-
sealed batteries. I think (not sure) it works at no more than 14.4
volts. This is it http://snipurl.com/chwx.

Is it ok to leave this charger connected until it trips out or will
the trip point be delayed by the presence of the car's elctrics in
the circuit?

The few times I've had to charge my car battery I've done so in-situ with no
problems. HOWEVER most el-cheapo car battery chargers are NOT regulated and
could seriously over-charge the battery if left connected for too long (they
may well taper off the current but still end up over-charging the battery).

If you want to be sure, you can buy an external battery charging regulator
that you connect between the charger and the battery. This not only
prevents over-charging but some also have indications on them to indicate
how flat the battery is and how the charge is progressing.