On or around Mon, 11 Sep 2006 22:30:12 +0100, Dave Gibbs
<
[email protected]> enlightened us thusly:
>Mine were much worse than that, I'm surprised I'd not had any small
>fires from it. The connector just fell to bits and the spades were
>black as can be. I should have photo'd them before I chucked them. I
>haven't delved deeper (yet) but I suspect that the spotlights that I
>removed from the bull bar were wired in the same circuit. Result of a
>previous owners wiring 'skills' which I'm slowly sorting out.
I bet someone fitted over-wattage bulbs at some point.
I've seen various melted and burnt things in vehicle headlamp circuits, and
mostly it was down to overloading the system. The headlamp circuits are
designed to take 60W per lamp and 120W total. Run 200 W or 260W though it
and you're overloading it getting on for 100%, hardly surprising that this
causes trouble.
modern motors seem even more prone to this, with minimum-spec wiring and so
forth. the older ones at least had decently-fat wires. Older light
switches seem more robust too.
The moral is, if you're uprating, even just fitting a pair of 55W spots, put
relays in.
Is it CANBUS that runs a fat power circuit around the vehicle and switches
everything locally? Makes sense, if you're doing a rewire - you can do it
electromechanically, too - doesn't have to be electronic.
Run a nice fat cable all round the vehicle like a ring main, and take
suitable-sized tappings off it for relays to power up lights and suchlike
wherever you need 'em, preferably without actually breaking the main power
line - I'd do it by stripping the insulation and soldering, making sure that
the joints are then properly insulated and more to the point, secured
against vibration. the various extant circuits which currently power up the
lights, etc., can then be used to trigger local relays. Put the relays in
sensible places where they can be got at and use fused relays (or possibly
fuses in the relevant tappings)
lessee, you'd want 4 relays for indicators, 2 for rear lights, 1 or 2 for
brake lights, 2 for side lights... they're all fairly low current, so a 10A
relay would do each. Then you want one for yer horn, one each for the 4
headlamp filaments, plus one for spots and one for fogs, if fitted. Spots
needn't have individual relays, you could run 4x55W or 2x100W from a single
30A relay. The headlamp ones have one each for redundancy, in the same way
that there are 4 supply wires on modern vehicles to the headlamps, and 4
fuses.
--
Austin Shackles.
www.ddol-las.net my opinions are just that
"Remember that to change your mind and follow him who sets you right
is to be none the less free than you were before."
Marcus Aurelius Antoninus (121-180), from Meditations, VIII.16
