This weekend I had a few hours to work on the plane. It’s been a couple months since I’ve spent a good chunk of time on it.

I decided to take off the old conventional master and starter contractors. I’ve decided to go with Vertical Power Primary Power System. This is a single unit that replaces the contractors, as well as current shunt and fuses. I’m also using the Vertical Power Pro solid state VPX. These two will work really well together.

For easiest access I mounted this on the edge of the firewall near the battery as far away from the exhaust as possible. Every bolt and post is accessible. I also crimped on the ring terminals for the alternator and for the starter once I had this mounted.

I also wired up the J1 harness that includes all the inputs for the master switch, battery and alternator current sense and fault indicators. This will all feed into my EFIS and be displayed on the engine monitoring page.