FOT needed on engine side of firewall?

Starting to think about the electrical and see there are field of tabs available with tabs on one side or both sides of the firewall. What on the engine side would need to be grounded to a tab. If it matters, I have airflow performance FI and pmags on an o-320, planning on a g3x and a VP-X

Jay

No, at least not from what I found building the 10.

probably not

I installed one on my RV8 (w/ G3x, VP-x & dual P-Mags). While the idea seemed good, I ended up with only two ground wires connected to it.

I have a handful of engine sensor grounds, a voltage regulator ground, and an EI ground. Probably 5 total.

No need...I have exactly one ground wire attached to mine

Using Fast-On type connectors anywhere on an aircraft is a terrible idea in my opinion. Yes, I know that Cessna used to use them, and that many RV's are flying around with them, but I have spent many O hours troubleshooting and repairing electrical problems on older aircraft due to these type of connectors.

For a few dollars more you can use terminal strips and ring terminals. You can install up to three wires in each ring terminal, and up to two ring terminals on each screw.

http://www.mcmaster.com/#terminal-blocks/=zc11q9

This is likely as contentious as Primer Wars, but the flip side is that screws holding ring terminals can loosen, causing intermittent or failed connections.

Neither is perfect.

Just a suggestion. This type of terminal block eliminates both problems. MS27212. Proper lock washers eliminate the terminal loosening problems with screw terminals also.

http://www.marcomanuf.com/PDF DOCUMENTS/aircraft catalog page.pdf

There are other common sources.

I installed the large 40 tab on the inside and am using most of them (ran a dedicated wire from everything ) and the small set of tabs on the firewall side. I think I am using 6 or 7 of the tabs but there isnt anything easier or better to organize the grounds. This really helped when I was looking for a possible bad connection related to charging issues. Made it fast and easy to eliminate all the ground connections as an issue, at least on this end of the wires.

I would do it again with at least 10 tabs on the firewall side.

Speaking of lock washers, split-ring lock-washers do not prevent loosening according to a demonstration by Nord-Lock. Are split-ring lock-washers used on automobiles anymore?

Nice Nordlock video!

Mich48041 said:

Speaking of lock washers, split-ring lock-washers do not prevent loosening according to a demonstration by Nord-Lock. Are split-ring lock-washers used on automobiles anymore?

Click to expand...

Lots of undocumented variables that effect the outcome of the demonstrations with respect to the video. Pretty much any screw fastener tightened to create a preload higher than the loads induced by the vibration will not loosen up. With respect to use for electrical terminals, the the failure mode for electrical terminal fastening is typically due to torque induced through turning of the screw by tugging on the wire terminal. Since the torque applied by the terminal can be higher than the tightening torque applied when screwing the joint together it loosens. If terminal blocks with barriers that prevent terminal rotation are used, it limits or prevents this problem.

Properly used quality fastons have fairly high forces associated with their connections and they work well until vibration and age weakens the spring tension of the female terminal. Then they can have poor contact area breeding gremlins to find.