David Lesher 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.

I decided that I should add some resistance just in case one of the
batteries (plane or charger) gets really low. I don't want a sudden
rush through it. Then I realized that if I'm going to do that I might
as well just use small connectors and wire. And if I'm going to do
that I don't really need to use the high-power port.

However...using the existing power port is handy. The best thing about
it is that it's externally accessible. I can put a charger on it
without leaving the nose open. I leave expensive stuff (headsets) in
the nose so even in my (shared) hangar it's worthwhile to keep it
locked, but it's especially advantageous if I'm on the ramp somewhere
leaving the cabin and engine and heaters on.

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.

See any problems with that?

Thank you.

--kyler