What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

What is this thing?

RV7A Flyer

Well Known Member
Patron
A friend is redoing some wiring FWF (Alternator to battery, contactor to starter) to replace the Tefzel with welding cable...this is what was in-line between the alt and the battery. What the heck is it? (He's putting in an ANL current limiter for the fuse, btw).

enhance
 
But I don?t think Bob recommended elastic stop nuts on electrical connections! Ummm....heat?:confused:
 
It is an inline fuse. That was what Bob Nuckolls recommended and B&C sold 20 years ago.

I gathered it was a fuse of some kind, just not one I've ever seen. A lot was wrong, IMO, with this installation: the "fuse" was entirely unmarked (no indication of current limit, manufacturer, nothing), it used Nylocks (not necessarily bad, but I'd have used all-metal locknuts), insufficient threads showing past the nuts, Tefzel wiring (stiff, tendency to break in this application well known), lugs were crimped AND soldered on the ends at the alt and battery ends, insufficient service loops. And yep, it failed just as you'd expect...the lug broke at the alternator.

In any case, just wondering what *precisely* this thingamabob was, if it had a name or something (other than "fuse").

ETA: I also think this would make a field repair a giant PITA if it were to ever "blow".
 
Last edited:
Tefzel wiring (stiff, tendency to break in this application well known), lugs were crimped AND soldered on the ends at the alt and battery ends,

Tefzel is the standard for aircraft wiring. I'm not aware of a tendency to fail in any particular application. As far as crimping and soldering the ends, that's a practice Nuckolls walks you through in "The Aeroelectric Connection", so I'm sure there are a lot of aircraft out there (including mine) which use that method on the big wires. Properly done, I don't have a problem with any of it, but there are a lot of ways to skin the cat...
 
I was going to use welding cable but then I compared the insulation with tefzel with an open flame. The welding cable kind of smoldered with lots of smoke. the tefzel did not. Also, lots of people solder those big lugs in addition to crimping, to keep the joint airtight, but you have to make sure the solder doesn't wick beyond the terminal. I did that on my big cables and I don't have any additional stiffness near the terminal.
 
Back
Top