On 26 Jan 2005 05:32:13 -0800, wrote:

Is it bad to leave a charger hooked up to the battery permanently. Mine
is a 12/2 with automatic operation.

Hi Don,

Well then, I must presume it is the inferior product to blame (or
perhaps inferior advice). Take note that Dave has an identical
installation and we both suffer no problems whatever and this is for
YEARS of sustained service.

Hawker guarantees my cells for 15 Years of life and fully recommends a
continuous float charge. There are probably 100 Million batteries in
hospital corridors, schools, churches, theaters, public service
buildings all sitting there on a float charge waiting to turn on the
emergency lighting. In fact my current limiting of the quick charge
is overly conservative as Hawker explicitly offers there is no
restriction to inrush current from professional grade chargers.

Lou's report of his buddy's charger running at 18 V is nothing short
of a death wish with a meter indicator. If you read the precautions
printed on that charger's box, it also says it is dangerous to charge
an automotive battery with it while the battery is still connected to
the automotive electronics.

If you choose to employ cycle charging (where you disconnect the
charger and run the battery down), then you need to run at a higher
charge voltage which is typical of most chargers off the shelf for
automotive work where you are doing a battery overnight. The higher
voltage is NOT GOOD for floating - unless you have deep pockets for
battery replacement. In the case of automotive batteries, their ONLY
use is to start the engine. After that, they are little more than a
chemical capacitor for the alternator's supply to the automotive
electrical system. In the old days, better cars had a dash mounted
Ammeter. The plus indication showed a slight positive indication for
the alternator load (charge and ignition in the days before megawatt
stereo systems); or a negative indication when you were running on
battery alone (and your -well in this case, and age- generator was
shot).

73's
Richard Clark, KB7QHC