Another light bar question.

[Disco_Stu]

Hi all.

I've aquired myself a light bar and four rectangular spots. Before fitting it I want to try to get a bit of info from you lads who already have them. I've searched through all the previous light bar threads and which have answered most of my questions, I've made some plans, this is what I have:

• +ve feed taken from secondary battery, -ve on light bar muonting bolt
• Wire ran up the snorkel with breather pipe so no need for a roof grommet
• 30A relay wired under dash where its hopefully dry, 20/25A inline fuse close to the battery to avoid voltage drop
• Dash mounted illumenated rocker switch, either 2 or 3 positions depending on the answers to my questions...
• Power bus type thingy along the back/insde the light bar and block/bullet/soldered splices to each lamp

My questions are:

• In order to wire my spots to work both independantly on a switch and to flash with main beam I believe its necessary to fit a diode. Where does this go and what, if any rating must it have?
• What is the consensus opinion on how far forwards/back the lights need to be mounted to make them more usable/avoid glare. They are underslung rectangular 55w halogens. My disco is black, a matt bonnet patch/chequer plate may be an option.

I know this topic has been done to death but I would appreciate any input that you lads can offer, feel free to point out anything you think I've missed also.

Cheers, Stu.

[J.D.]

No you don't need a diode to do that and yes a matt black patch is advisable, particularly if you have a metallic paint job. Mine are as farback as the lightbar would go on the roof.

[stuntman]

Yup I agree with the above, no diode needed.

The relay needs it's trigger switch, ie one of the 'on' positions to trigger it, you then run a second trigger/power lead, to your other 'on' position and bob's your uncle etc etc.

[karlo]

Evilgoat posted a diagram to do this have a look see if its in his gallery if not I have it.

[LittlePaul]

Evilgoat posted a diagram to do this have a look see if its in his gallery if not I have it.

Not there, can you put it on yours?

Cheers, Paul

[Disco Matt]

On mine, the full beam feed wire was blue/white. Never sure how standard these things are but that's a good starting point.

Yes you will want a matt black patch on the bonnet. I've had to angle mine up a long way to reduce the light spill on the bonnet to a manageable level. If they were pointed any further up they'd be a hazard to aircraft!

"Barn doors" as found on stage lighting might be an option - these are black metal hoods fitted to spotlights to stop the light creating unwanted shadows. They might well look somewhat daft however!

[karlo]

Click To Enlarge.

we'll get to the fuse in a moment. Wire the main beam feed to one of the outer pins of the switch, the other outer goes to the side of the fuse you fitted furthest from the battery so the fuse is between it and the battery. You might want to add a VERY low rated fuse in here, 1A would be generous, to protect the switching circuit. Wire the center to pin 86 of the relay and wire pin 85 to ground.
Wire a fuse from the BATTERY to pin 87 of the relay. Then connect your spots to pin 30. Use an on-off-on switch and you will have:

On
Off
On with Main Beam.

The Fuse
Find out the wattage of your spots and add them up. so In my case I have 2*100W so thats 200W, simple eh?
Now divide that by the voltage
so 200/12 = 16.6.

Nearest fuse is 15A, that will blow. Also you need to allow a reasonable margin for surges and in a -V switched system, the relay too. 20A would be resonable here. With larger spots make sure your relay is up to it too!

[Disco_Stu]

Thanks for the replies so far, I think I've said before that I'm not at my best when it comes to electrics, no experience  :oops: When I worked in a garage if it was more complex than fitting a stereo we called in the mobile auto electrician and left him to it!

Stu.

[gamekeeperjames]

where can i get these bonnet patches from or are they things people make themselves.

cheers james

[BILKO]

For bonnet black vinyl patches try Lee at customvinly.com