ground loop theory vs reality

[bobmarkert]

Gurus,
Thanks to the many posts on this forum, I understand the theory of electrical ground loops and what causes them. I'm now at a decision point in my electrical system build and I find I don't know the practical application of this knowledge.

I intend to run a grounding strap from my engine to the firewall.

In the pictures below, you can see where I intend to mount the Ground block "farm" on the avionics shelf behind my panel.

Here is my question:
Should I run a wire from the bolt on the grounding block to the bolt on the "firewall ground" to tie them more directly together or just let the connection on the avionics shelf suffice?

Any other suggestions are also welcome








Thank you all

[rv7charlie]

I think that if you look at info on the Aeroelectric Connection, it will show that most builders place the 'forest of tabs' ground block on the firewall, with a brass or copper bolt going through the firewall to another ground array bolted back to back with the one in the cabin. That achieves the 'single point ground' you need to avoid ground loops (which really means multiple paths to ground).

Mounting them a few inches apart would probably be fine, but it's pretty easy to go whole hog & do it right.

Edit that; this is an -8, right? I can see why you might want to avoid the firewall mounting position. Perhaps you could 'float' the forest of tabs & run a heavy ground wire from there to the firewall ground point. That should get you almost the same effect, and getting all the audio & RF stuff to the same point is most of the battle.

Why not email Bob Knuckolls via the Aeroelectric list & ask his opinion?

Charlie

[skylor]

Originally Posted by bobmarkert

Gurus,
Thanks to the many posts on this forum, I understand the theory of electrical ground loops and what causes them. I'm now at a decision point in my electrical system build and I find I don't know the practical application of this knowledge.

I intend to run a grounding strap from my engine to the firewall.

In the pictures below, you can see where I intend to mount the Ground block "farm" on the avionics shelf behind my panel.

Here is my question:
Should I run a wire from the bolt on the grounding block to the bolt on the "firewall ground" to tie them more directly together or just let the connection on the avionics shelf suffice?

Any other suggestions are also welcome








Thank you all

As a datapoint: I too have an RV-8. I essentially did what you're suggesting. I mounted the forest of tabs on the panel side of the lower baggage bulkhead and ran a cable (8 ga or 10 ga...dont recall) from the large mounting bolt on the forest of tabs to the firewall where it is fastened to a bolt that also secures the firewall end of the engine ground strap. I have absolutely no noise or evidence of ground-loop issues in my plane (240 hours on the Hobbs).

Skylor