Wiring Alternator and EMS – Jared and Tabitha's Bearhawk Construction Log

I was getting ready to install the ailerons and I realized that a few of the hinge mounts are missing nut plates. I riveted those on and added the ailerons and right flap onto the wings. I ran the control wire from the alternator back to the switch and crowbar overvoltage circuit breaker. I’m using separate toggle switches for the master and alternator, which is different from the split style switch that is more common in production airplanes. I connected a few more wires, including the serial update wires for the D100 and D180. These serial ports are for updates to firmware and such.

EFIS Wire Spacing — Here you can see my wooden mock EFIS. The Garmin products make electrical connections on the back of the mounting racks, while the Dynon producs make their connections on the back of the actual unit. In the Dynon case the leads have to be a bit longer, and this arrangement helps me keep them uniform. These three wires that you see here are for the serial port.

Enclosure — This little box houses the low voltage and audio amp circuits that I made. It also supports the serial connections for the Dynon boxes, as you can see on the lower left.

Lycoming Accessory Section — Here's a nice reference picture of the accessory case, with the SD-8 in perspective.

Lycoming Oil Pressure Port — The little red plug in the middle of this picture is where the oil pressure sensor connects. The nipple can't go in with the engine on the mount. I remember reading that once, but I didn't think to put the nipple in before I hung the engine. It's not a big problem, since I'll certainly have the engine off again later.

I’ve been spending more time with the wiring instructions for the Dynon units, and at this point I have most of it figured out. One big question mark is how to attach the single compass sensor in my dual installation.

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