Shane writes:
>Now I'm confused! Could Dan masters or Tom O'Malley please help out
>with this one? Bob, IMHO, the Lucas 35-amp and BUSS 35-amp fuses *should*
>be equivalent.
Ah! You've come to the right place to ask this...
British amps, like British subjects, spent many decades traveling in
the wrong direction. When the big polarity switch-over came in the
mid-sixties the poor little UK electrons got confused and became
disorientated. Today they travel on the left side of the wires, but
only under protest. With their loss of spirit, so went their strength
to a mere fraction <50%> of what it used to be. Hence the 35/17 amp
marking you see compared to domestic amps.
Oops! Sorry....we're still in the holiday spirit around here.
Ahem... :-)
Seriously now...
>I am sure there are a lot of people out there (like me) running
>non-Lucas 35-amp labeled fuses and perhaps we should'nt!
No...don't do this. The ratings *are* different. I think Bob Harris
was right on target when he speculated about the frequent LBC wiring
meltdowns. A domestic <United States> 35 amp rated fuse is not the
same as the LUCAS 35/17.
Dan had an excellent post a few months back on British wire sizes.
It seems the current carrying capacity is not rated on the basis of
overall wire gauge as is done here. <16awg, 14awg etc.>
Instead, they rate the wire capacity for the number of fixed diameter
strands in each wire. Interesting. While I haven't actually tried to
measure them I know there's nothing large enough in my Spit to handle
35 amperes continuously...save the battery cables that is. :-)
Yet my Haynes manual just says "35 amp fuses"....scarey!
>What sort of fuse should we use?
Why Shane!!.....GENUINE LUCAS of course. :-)
I still have Lucas 35/17amps fuses in my Spit, but if one popped on a
Sunday night in the middle-of-nowhere I'd replace it with a domestic
15 or 20 amp automotive fuse. I don't think I'd find a 17 amp fuse in
the local parts store.
Would the domestic 15 or 20 amp fuse have the same surge rating as the
original Lucas 35/17? I don't know. :-)
> Why dont fuse manufacturers label their product as being for peak or
>continuous ampage?
My experience has been that all domestic <U.S> fuses and circuit
breakers are clearly marked for continuous amperage. Other
characteristics like time delay/fast-blow or voltage may be marked but
often require a peek at the data sheets to get the complete story.
> Does this mean all cars use fuses that are not rated for continuous
>ampage, or is that a Triumph/Lucas glitch?
AFAIK, domestic and Japanese automotive fuses are marked for
continuous current. I don't have enough experience on other foreign
marques to draw any conclusions. A wise engineer one told me that the
French copy nobody, and NOBODY copies the French. :-)
>Helllppp!!.
Now take your Pantera...I'll bet *that's* interesting. All those
EYE-talian electrons buzzing 'round that Ford V-8. :-)
> Shane Ingate about to blow a fuse in San Diego
Cheers!
Tom O'Malley
'74, '77 Spits <with GENUINE LUCAS fuses>
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