Driving lamp wiring???

Run the wire up through the snorkel?

Martyn

Thanks but no Snorkel is fitted !!.

I intend fitting a Roof rack to my 90 and thought the extra lighting would come in handy off road.

Drill a hole and use plenty of cable ties to keep it neat? ;)

On a more serious note, you could use some kind of cable conduit as sold by the likes of Maplin and RS I guess, and then run all the wires through that. If you didn't want a hole in the roof you could then run that down a windscreen pillar (secured by P clips) and under the edge of the bonnet. Not sure how well that would stand up to a battering by trees etc. though if you do much in the way of laning.

Paul

-- Paul Everett repton at repton dot org

Well that is the beauty of my series 3 I don't need to drill any holes, it has plenty to be getting on with :)

On or around Thu, 02 Oct 2003 22:02:25 +0100, Zen enlightened us thusly:

erm...

depends how much hassle you want, but if you want it all hidden... up one of the pillars into the roof, and thence through a hole in the roof with a very good rubber grommet to seal it, alongside the leg of yer roof rack.

remember you need a relay to operate more than 2x55W additional lights, if you're going to run 'em concurrent with the main beams, and remember to install a fuse in the supply.

Just got a pair of Ring Rally Giants for the 110. proper steel lamp shells, reasonable fittings and about 25 quid cheaper than the new-fangled plastic equivalent - also slimmer, which is relevant when fitting 'em to the bumper, as they don't stick out further than same.

If you have a rack fitted then all you have to do is take the wiring along the inside to the B pillar. You will find just enough room to bring a cable out at the top where the metal is folded. Then up a rack leg and along to the lamps.

And it needs to be a fairly hefty relay (4 driving lights with 'legal'

It may be worth doing a search of the Camel Trophy site(s), where it's pretty mandatory to have as many lights on the roof as will fit in the space :-)

Martyn

On or around Fri, 03 Oct 2003 22:31:32 +0100, Mother enlightened us thusly:

hehe. wonder how many of them are correctly wired...

but a 30A relay should run 4 lights, and they ought to be able to earth through the body (might need a proper earth connection from the rack to the roof, depending on how it's fitted) so only 1 wire need go up the pillar.

I notice that putting the headlights on with my newly-fitted pair of spots (nice visibilty at night now) drops the idle speed by 50 rpm, which calls to mind the thought that if you're putting more than a couple of extra lights on then you need to keep the alternator output in mind. Fine on the new stuff with 90 or 100A alternators, but older ones might need a bigger alternator. Standard SIII was only 34A, I suspect, and the Range Rovers gradually grew - early ones are 34A, 75-59 are 45A, 80-on are 65A, and later ones 80A. so later ones would be OK, but early ones are not gonna be so good. Discos seem to be 65, 80 or 100.

start fitting 6x100W bulbs, for example and you're looking at 50A to drive 'em, even with a 100A alternator, it's not going to keep up unless the engine revs are up around 2000.

Roof-mounted spots are, from what I hear, a mixed blessing for off-road use

- more light, but from a funny direction, and they can apparently tend to "flatten" the ground by removing the shadows from holes. Open to question how much an advantage/disadvantage this is - the other point which is an advantage is that they're not prone to get covered in mud or be underwater.

Thanks for all this guts.

I think after reading all these the best solution is a cable through one corner of tghe roof. (drivers side) and then down the A Frame.

It will only need the one feed as the earth can be taken from the roof rack that I can electrically bond to the roof.

Thankls again

You won't have any problem getting access on the inside. The trim will self remove for you :-)

Well... I'd be very careful about the earthing. I'm not too sure what you mean by "electrically bond". What is the roof rack made of?

Mind, I guess if the earthing isn't that good, an electrically bonded weld may be the result! :-)

Martyn

Dunno anyone who's ever been silly enough to do such a thing, no, no, no...

Nobody, not even remotely, springs to mind...

Nup...

I wouldn't...

Not even 20++ odd years ago...

nope...

Not me...

Certainly not on a Thames van...

;-)

Martyn

On or around Sat, 04 Oct 2003 21:26:58 +0100, Mother enlightened us thusly:

probably means an earth wire... but in fact, it depends on how the roof rack is mounted. if it's bolted on through holes in the body etc., it should probably earth OK unless you've got too much paint in the way. If it's clamped on to the gutters, then it likely won't. however, a short earth wire from the roof rack to the body would solve that.

On or around Sat, 04 Oct 2003 21:30:10 +0100, Mother enlightened us thusly:

big ++ if it was a thames van, havent seen one of they for decades.

and that probably had a dynamo anyway :-)

It's one of the few vehicles I've had that made a 101 seem spacious

oh those were the days :-)

Martyn

In article , Mother writes

Hmm, let's see... 4x55w = 220w @ 12V = 18.3A

But (and it's a big 'BUT') there's the not-insignificant matter of inrush current. Filament bulbs are power-rated at their operating temperature (& voltage). When cold, they have very significantly lower resistance. Putting an AVO on a new 60/55W halogen headlight bulb gives a cold resistance of only 0.1 Ohms* So the initial switch-on current would theoretically peak at 120A (1440W) per bulb!

Yes, that really is an instantaneous peak of around 500 amps for the four bulbs. In comparison, my MIG set only goes up to 120A. Inrush is the only argument for thin wiring - gives you a natural soft-start to preserve bulb life!

So Martyn's pretty much right (per usual, I'm coming to realise!). You will at best get nasty accelerated corrosion at the contact points if there's any appreciable resistance, and at worst start spot-welding and/or blowing holes in things.

If you want good light and reliability, use good-quality copper cables. Those multi-stranded loudspeaker cables would be good in this application, but might need some insulation reinforcement at rub points. Check the spec in Ohms-per-metre, and look for the heaviest insulation. Many-stranded cables cope with vibration and flexing much better than

Regards,

Simonm. (*I think I was testing the 60W filament. You get very inaccurate results doing this (could even be lower than that). A digital multimeter is usually pretty useless as it's too high impedance. YMMV, of course.)