April 4, 2020

Main Wiring Harness

I finished adding all the needed wires to the main electrical harness. Now, I can begin adding terminals to the wire ends, and for some of the connectors, putting the terminals into the connectors. I have to leave some connectors off until the harness is installed in the fuselage because the harness passes through some lightening holes that are too small for a connector body to fit through.

I will have two major harnesses – the first one, which I am calling a “spider” harness, has all of the power and data signal lines. The second harness is just the analog audio lines that run to the center armrest for the headsets. RF coax lines for the comm and transponder antennas will be run separately.

Main “spider” harness contains all of the power and data signals

The next few photos show some detail of building up the connector for the roll servo. Because the servos are daisy-chained, there are several splices to make: CAN, power, AP disconnect. The two shielded wires (CAN, trim servo out) are supposed to be grounded to the backshell. I spliced in pigtails for this, but I don’t have the hardware in stock yet; crimp ring terminals and #8 screws will be arriving some time this week. Garmin also recommends using silicone fusion tape around the wire bundle underneath the strain relief, so I ordered a roll from Aircraft Spruce and will touch up the connector when it arrives.

As I add the connectors, I’ll also be removing the zip ties and replacing them with lacing cord, as you can see in the last photo below.

Stripping off the jacket on the shielded CAN lines
Joining the shields, and adding a pigtail that will attach to the connector backshell
Splicing together the CAN high and low lines
All terminals inserted to the connector, ready to close up the backshell. You can see I have one of the splices inside the backshell, which is not correct – I have to go back and fix this
All set, except for the shield drains (waiting for ring terminals to arrive)

One thought on “Main Wiring Harness

  1. It looks like your short About 8000 wires if my RV8 is a good example. (It’s probably not, you’re probably smarter than I was.). 🙂

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