All I found on Aerolectric site were ref. to low-current apps for
fusible links, using #24-#22 wire. Did I miss something else?
Generically, I found elsewhere they're used lately in autos in the
feed from alternator to battery. They say a 60-amp alternator can
dump into a discharged/defective battery more and for longer than a
appropriately rated circuit breaker can handle, meaning a more $$
time-delay breaker is what is otherwise needed. So it's an apparent
cost issue to just size the feed wire to just melt. Rationale
otherwise not clear to me, but curious they must melt often enough so
that a fuse-like replacement is on display at auto stores. The Rotax
whirlygig would seem of insufficient output for this solution.
Littlefuse.com has a tech brief with further issues, but their link
product is similarly for high-current apps (80-250A), where breakers
are $$. Cited also is the nonuniformity of the melting point of link
wire (should be like zinc, not garden copper), but maybe Nuckolls
knows Mil-Spec wire is more predictable. One problem I see is having
a wire that can potentially heat up red hot to short of liquid,
destroying the insulation, cool down and still work. Not in my
airplane, thank you.
All I found in quickie look; just the messenger.
Best,
Fred F.
> >Most contact breakers are effectively slow blow fuses due to the way that
> >they work.
> >
> >Anything other than a contact breaker would be a liability as the main fuse
> >in an aircraft electrical system (ie if there were a surge you would loose
> >all your electrics and changing fuses in flight is not an option - asuming
> >you have a spare !)
>
> Bob Nuckolls recommends fusible links, so that is what I will use in
> future. I've yet to read anything of his that I can't respect and he's
> brighter than me anyway.
>
> Graham
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