[Mike]

i've got 700watts in lighting that i need to wire up aswell as a thermo fan
i wan't to run them on a seperate circuit (straight to the battery) so if something goes wrong it won't effect the rest of the car
because i'm doing it that way do i still need relays?
also should i put the fuse on the battery side or the light side of the switch?

Cheers
Mike

[Rockhopper]

No, you don't need relays if you are wiring straight from the battery.
Put the fuse as close to the battery as possible.

[Mike]

what amperage fuses should i use for a thermo fan and 100watt lights?

[hobzees4wdshop]

Amps = Watts/Volts

Work out how many watt the fan is and do the maths then go slightly higher.

If your fan is 150w plus 100w of lights =250w

zook voltage = 12v

250/12= 20.83amps
A 30amp fuse should be ok for this setup but if you are running 700w of spotties + thermo.....

850/12 = 70.83amps - thats one mother fuse ur gonna need.

Overkill maybe...why not think about HID...low current draw more light.

With any loom upgrade you should run relays...its the only way to incorporate the switching mechanism into your lighting with full battery current. You can make up a loom that plugs straight into your H4 plug that goes into the back of your headlight, this gives you the switching plus direct battery current.


this gives you an idea of a spotty loom setup with direct battery current.

Dan.

[royce]

get a decent fuse panel that you can run 1 fat wire into and then smaller ones out to your lights an so on via relays (yes you need relays, the switches WILL melt and the extra wiring length will leave you with dimlights)

the fuse protects the circuit against shorts not the lights from drawing too much current so need to be close to the battery and rated slightly lower than the cable

I would run a twin (power and earth) 4mm2 like hella 8848 (this isnt 4mm automotive size) for each pair of lights and the same for the fan (jsut cause youll already have some with a 20-30 amp fuse on each circuit (you will have 3) then a relay for the fan switched however you want and a relay for each pair of lights switched through high beam

[Rockhopper]

hobzees4wdshop wrote:

Amps = Watts/Volts

Work out how many watt the fan is and do the maths then go slightly higher.

If your fan is 150w plus 100w of lights =250w

zook voltage = 12v

250/12= 20.83amps
A 30amp fuse should be ok for this setup but if you are running 700w of spotties + thermo.....

850/12 = 70.83amps - thats one mother fuse ur gonna need.

Overkill maybe...why not think about HID...low current draw more light.

With any loom upgrade you should run relays...its the only way to incorporate the switching mechanism into your lighting with full battery current. You can make up a loom that plugs straight into your H4 plug that goes into the back of your headlight, this gives you the switching plus direct battery current.


this gives you an idea of a spotty loom setup with direct battery current.

Dan.

That is correct, but from what I understand Mike wants to run the driving lights on it's own circuit without interfering with the cars circuits, which is why you wouldn't need a relay if you were wiring them up directly to the battery, but yes, Royce is also correct. The switch can melt, and the driving lights would be dim. You could put a heavy duty switch in to handle the current, but you will still have the dimming problem. Also, I'm not sure about other states, but in NSW, if you don't wire the driving lights into your high beam circuit, then the lights become illegal and you could be defected for having them.
As Sierra headlights switch oppositly to most other cars (if that makes any sense) I've had to wire the driving lights up a little differantly in regards to the above diagram to work. The following is a quick circuit diagram to how I've done mine.


Of course, splice your own wiring into the rb and the rw wiring on the plug, and solder your wiring in (don't just twist the wire around or god forbid scotch lock), and make sure you use insulation tape to prevent any possible shorts.

[royce]

why do you have the lights earthed to one of the coil terminals on the relay?
why do you have the same terminal wired to the low beam pin?

the correct circuit to trigger a relay on every car in the world with a 3pin headlight plug is to go from 1 vertical pin on the plug>pin 85 on relay, pin 86 on relay>terminal on dash switch, other terminal on dash switch>other vertical pin in headlight plug

no matter if the headlight is positive switched (like most australian cars) positive activate and negative dipped (Suzukis) or constant positive and negative activate and dipped (Toyotas mostly) this setup will always work as the only time those pins will have power on one side and earth on another is when the high beam is on.

dont be fooled by the low beam wire showing power on high beam, you are getting a dodgy feed the low beam filaments (unplug the lights and watch the power go away) that switches off when the lights are off, on a toyota the spotties would turn back on

[Rockhopper]

Firstly Royce, thanx for making me think first thing on a Sunday morning. Me head hurts now, and I think I'm even more confused
It's been a while since I've wired them up, but I do remember swearing and cursing for a while to try and figure out why the driving lights were'nt coming on when they were supposed to and why they were switching themselves on when they were'nt supposed to.
I've just gone back out to my car to figure it out.
The reason I've wired the driving light earth and low beam wire to the same pin on the relay that the low beam wire acts as the earth when switched onto high beam. It was the only configuration I could nut out that would work when I wired them up. If I were to get my test light and check the power at the headlight plug, with the headlights off I'd be getting power at both the red/white wire (low beam) and the red/black wire (high beam). If I were to switch the low beams on, the red/white becomes an earth and the red/black has 12V+. If I were to switch the high beams on the red/white becomes 12V+ and the red/black becomes the earth. This in turn powers the relay up switches the driving lights on.
Does that make any sense, or are you guys just as confused as I am now.

[Rockhopper]

I'm still scratching my head. After sitting here and looking at Hobzees wiring diagram, theoretically, if I were to wire the lights up this way, it would work on the Sierra, if I connect pin 86 of the relay to the red/black wire on the headlight plug which is an - when the high beams are on. Is this correct??
Sorry bout the hijack Mike.

[royce]

you cant think of headlights as 1 earth alternating power to switch high and low, they are 1 power 2 earths to switch high and low

unplug both headlights and re test what you have, you would of been measuring 12v through one of the filaments, this will go away once you unplug the circuit being made by the headlights

tapping the vertical pins, one power, one earth always works

[Rockhopper]

yep. You're right. And to answer my own question, I went out and rewired my driving lights as per Hobzees diagram, and it worked. Not sure why i could'nt work that out in the first place. Must of been tired and emotional when I wired them up the first time (little one was teething).

[JrZook]

hobzees4wdshop wrote:

Amps = Watts/Volts

Work out how many watt the fan is and do the maths then go slightly higher.

If your fan is 150w plus 100w of lights =250w

zook voltage = 12v

.

Just to be picky i would say most car voltages are actually 13.8-14v. I have seen a few ppl get unstuck when using the 12v theory.

Dan