Dual Battery Single Alternator

[Charles Davis]

Structural work on N138CM is complete.  

I'm trying to strike a balance between weight, cost, and redundancy.

I'm planning on the following avionics, instruments, electric:
>Efis/Lite Plus G4 with 2-axis autopilot
>2.5" steam gauge backups (t&b, airspeed, altimeter)
>vertical card compass
>clock
>VM1000 engine analyzer
>one Com with flip-flop
>Xpdr
>no vacuum pump
> one mag plus Rose electronic ignition
> Cheap GPS velcro'd on the headrest to keep the GIB amused, and that I could snag in an emergency.  
> hand held radio as a comm backup
> XM Satellite radio for entertainment.
>LED internal lighting
>Whelan strobe
>landing and taxi lights on wig-wag circuit

I'm thinking dual battery, single alternator.  The idea is that I could switch between Batt-A and Batt-B to ensure both batteries get used on a regular basis.  The non-primary battery would be charged from solar cells embedded on the nose access hatch.

This minimizes my weight after of the firewall, and moves as much weight up front as possible.

Has anyone else used this configuration, and do you know where I might find a schematic?

I hope to be flying later this year!

Thanks!

FYI, here are the specs:
LongEZ, 0-320 E2D 150HP, day/night vfr.
Roncz canard, Davenport nose, Long rudders, front brake cylinders, wortmann legs, Grove high perf brakes, Wilhelmson nose lift with AEX, electric speed brake, standard Rutan warning system, oil cooler heat system, downdraft cooling.

[wvshoem]

Charles,

My Long-EZ will be similarly equipped. I will be running two EFIS Lite G4’s, one of which will have a back-up battery running through a diode. I ordered and installed the setup the Richter calls out on his web-site. He includes a wiring diagram – very simple.

The theory is that if the ship’s power is lost, back-up power is supplied, automatically, to the G4 from a small 12V battery (I believe it is 2 ½ x 3 x 5 inches) for more than two hours. Between that and a hand-held radio I should be able to safely get the airplane down and serviced.

I plan on using my plane for light IFR an am comfortable that this system can safely get me out of the clouds and onto the ground. It is certainly more backup than I currently have in my Cherokee 235 which I fly IMC all the time.

Have you installed your oil heat system yet? Care to share what you’ve done. I plan on installing a small heat exchanger in the hell hole and blowing the warm air forward.

I also hope to fly later this year.

William

[Charles Davis]

I don't have any pics yet.  But I will open a separate thread to discuss what we plan.