battery charger to get through Piper power port?

Kyler Laird writes:


{Switched power port}


I'm trying to grok how this works. What comes to mind is a 3-ping
connector: Hot, Ground, Control. Put +13v on the third pin by having
it jumpered to Hot WITHIN the cable's plug and that will do it.

You can then put a diode in series with the control lead so as to NOT
close the relay if the polarity is backwards. (Doing so would result
in what a former cow orker called "Big Sparky-Do's"... as the two
13.8 v sources would be in series with the only resistance being the
wiring and contactor..) A diode in series with the main lead with a) need
to be BIG... b) introduce unwanted voltage drop.

But is this how they did it? Suspect not...


3.. Best solution! Have your mechanic change the Positive lead from
the Piper plug so that it goes around the solenoid and directly to the
battery... This is how I have Fat Albert The Apache wired (and every
airplane I have ever owned) for charging and jump starting...

You had no problem with that?! Cool! I wanted this anyway because I'd
like to make a 12VDC tug and the power port is sitting right there just
begging to be used. (Having my tug not start recently makes this even
more enticing.)

Err. reverse polarity protection? And a short at the external cables
may start a fire inside....


--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433