Kyler Laird writes:

I don't suggest this lightly, knowing the BS and $$, but have you
considered adding a 2nd jack, smaller in size? That COULD be fused
at say 60A, and live. That could accommodate both a charger, or your
power-tug, with no risk to your aluminum friend...or you while in it.

Standing at the plane a few nights ago, I considered the same thing.
I've been working on blending a small charger and some old batteries
(from my electric lawn mower) to make a compatible charger.

What you want is a trickle charger; it need furnish only say 100mA
or so. (This assumes you religiously plug it in while hangared, of
course. Same scheme as most firetrucks.) A common source is the
residential alarm industry; they use a small PCB with a regulator
and a wallwart transformer. {I'll give you one if you need it.....just
to do it safely..}

I decided that I should add some resistance just in case one of the
.....
Good!

However...using the existing power port is handy.

My point was: "using AN external port is handy.."

Perhaps the answer is to bridge the relay contacts with a low-current
toggle circuit breaker? That would allow me to easily control whether
or not trickle charging or discharge can occur through the port but if
I happen to leave it enabled and a short or reverse polarity condition
occurs the circuit would be broken.

If you do that; the "ground power" contactor will close and stay closed;
costing you your protection. Hmm, you'd need a SPDT switch I think but
I'd want to draw it out. Not undoable, and perhaps cheaper than a 2nd
hole in the skin, etc.
--
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Unless the host (that isn't close).........................pob 1433
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