(John_F) writes:

What you need is a REGULATED lab power supply that has adjustable
voltage and current adjustments. I use a 0 to 33 volt at 0 to 30
amp power supply that has digital readouts for voltage and current
that I bought surplus.

The last thing a pilot wants in a hangar is a lab-grade supply. They don't
tolerate abuse well...

The regulator-modules I referred to, such as
http://homesecuritystore.com/ezStore123/DTProductZoom.asp?productID=1037
or many other units, produced regulated 13.8v/etc to charge the
battery. I'd not worry too much about current limiting; the wallwart
powering it helps there..and the regulator will as well. (The units
typically produce an amp or two at best; & with most wallwarts, far
less....)


You cannot feed the power into the APU port for a long time (more than
10 minutes) or it will generally fry the APU port relay because most
are not rated for continuous operation.

True! That's another reason I did not suggest such. It's a Bad Idea.

Install a charging jack on an inspection panel and wire it direct to
the battery with a FUSE at the battery that will support the expected
charging current from your power supply.

This is an approach as well. But the OP likely wanted to avoid drilling
more holes in his aircraft....I wonder why?

These voltages need to be adjusted some what if the
temperature is not close to 70F. This voltage verses temperature data
can be found on the internet for the type of battery you are using.

True, but you can just err on the low side; you do NOT want to
overcharge the battery. Note the alternator does not know the battery
temperature, either.


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Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433