[alpinelakespilot2000]

My Dynon DB37 harness has 4 generic black wire grounds coming from pins 3, 5, 16, and 17. How many of these should go through the firewall?

I've read the Dynon manual where it suggests that they might be used for "sensors" FWF that share a connection with the Dynon . However, I don't really understand the description Dynon provides. What "sensors" am I likely to need these grounds for?

My firewall wiring pass through is starting to get crowded, so if I don't need all four ground wires passing through the firewall, that would help me a lot.

Thanks for any help.

 

[Rivethead]

Canopy open closed sensor, Flap position sensor, Temp sensor and others.

 

[Dynon]

The grounds are just normal aircraft grounds. The wires may make hooking things up easier, but if it makes it harder, just ground things locally to the engine or airframe. A few of the sensors like fuel flow, manifold pressure, and fuel pressure do use grounds.

 

[alpinelakespilot2000]

Thanks guys, although I don't have any extra fancy sensors, it sounds like it would be prudent to pull at least 1-2 through the firewall. Even removing the other two will help free up the necessary space.

 

[uk_figs]

may not be needed

If you have built the system like many of us you will have a ground tab bar on both sides of the firewall where the ground strap goes, grounds needed on the firewall side can go here so you do not need to pass the wires through the firewall. This is a common grouns and also can make the wiring easier and tidier.

 

[alpinelakespilot2000]

If you have built the system like many of us you will have a ground tab bar on both sides of the firewall where the ground strap goes, grounds needed on the firewall side can go here so you do not need to pass the wires through the firewall. This is a common grouns and also can make the wiring easier and tidier.

Thanks Dave, but actually I don't have one of the Nuckolls-type ground tab blocks forward of the firewall. I have so few grounds FWF that I didn't think it worth spending the money, so I only have a brass stud going through the firewall to serve as my main ground.