LED Light bar install

[mgladwin]

Hi everyone,

Just purchased a LED light bar from eBay and have a few questions before I wire it up.

In my D40 I have the start battery in the front and the 2nd battery in the canopy. They are joined by 6 B&S cable with a Redarc Smart Start solenoid mounted near the start battery in the front. The light bar will be installed on the front of the roof rack on my canopy.

The light bar draws 15amps at 12v (180W) which is a fair bit.

It will be hooked into the high beam wire for legality and have a seperate switch to separate it from main high beams.

So im thinking its easier to get power from the 2nd battery in the tray as this is an easy run to the light bar on the roof rack. But, is drawing 15 amps from the 2nd battery a good idea? From what I know of the alternator and redarc isolator type setup, I wont be putting in enough amps to compensate for that amount of draw. With that being said, I am upgrading to a D250S Dual (20 amp DC to Dc charger) as soon as funds permit so I need to bare this in mind.

So really mains questions are:-

Should I get power from start battery and run at least 6mm twin? cable from the front battery to the relay in the canopy and then to the light bar?
or
Should i get power from the 2nd battery and run cable to the relay and then to the light bar which would be a much shorter/easier run?

I have to run the high beam wire from front to back anyway although I could mount the relay in the front I guess. I think I will mount relay in the back though as this means I can just switch the high beam wire in the cab easily on the way through to the back.

Distance from front to back is probably a 5-6m run once I have gone through where i need to etc so not sure if this is to bigger run to get power from the front?

Any help or ideas appreciated.

Cheers Martin.

 

[BJJ84]

I think charging wise it would depend on how your dual battery system works. I've never looked at them so I don't know, but if the alternator charges both batteries - assuming it can't do both at once but charges one til full then charges the other, it wouldn't matter which battery it's connected to as the alternator will still put the charge back. If that's the case, I'd run it off the rear battery as it's a shorter run for the heavier cable if you mount the relay in the back then it's just a small switch wire from high-beam (plus your over ride switch)

 

[Aussie Frontier]

I have a similar setup at the moment. I have the battery isolator in the tub as well as 1 small deep cycle battery and when playing at racetracks a much larger AGM battery.
I run the power to the lights from the back battery as once the battery isolator sees the alternator output go above 13.8volts its connects the 2 batteries together essentially.
I ran a 7 core trailer flex from the cab to the tub to basically do all the control for lights batteries compressors etc.So I was able to just extend the high beam light circuit into the tub.I used a relay to switch the high current and so far no issues at all and if your going to put in a separate switch then the current will come from the AUX battery and not your main

 

[sparra04]

Not sure bout SA but in NSW its illegal to have roof lights attached to headlight circuit
I run mine directly from cranker, straight through a relay and switch mounted on dash
As for cable run you want the thickest cable possible with the shortest run possible to combat voltage drop
If your intending on only using lights when alt is charging you should be ok

 

[Aussie Frontier]

Hey Sparra we used to be same but by the NCOP or VSB14 whatever its called we can actually run lights up top however no light can enter the cab or shine off the bonnet.Now NSW has taken its own take on the NCOP as in the 15mm vs 50mm for tyre size etc but I think they might now be legal.
Dont quote me on it but if they are now legal in the Anal center of the country ,the ACT ,they may have become legal in NSW

 

[TigerST]

Yeah roof lights have always been legal in NSW just another myth law made up. As long as they are wired in the hight beam with a isolation switch.

 

[sparra04]

Yeah roof lights have always been legal in NSW just another myth law made up. As long as they are wired in the hight beam with a isolation switch.

its funny all the responses you get
i rang rta on 2 occasions
1st call i was told they are illegal full stop
2nd call less than an hr after i was told as long as they are not used on road AND they are NOT wired into headlight circuit they are fine as they are deemed an auxilary light,not a driving light
taxi and police cars dont have there side facing lights wired into headlight circuit?
i then spoke to a mate who has extensive 4wd mod experiance(owns a 4wd workshop) and he also stated as long as they are not wired into headlight curcuit they are fine
that comment was also backed up with checking a mates taxi side lights
thats why i didnt wire mine to headlights

somewhere out there is the truth
its just frustrating trying to get the correct awnser
i think i got it in this case
cheers

 

[TigerST]

I'd like to see where is is writen down.

 

[mgladwin]

OK so consensus is grab power from the 2nd battery.

These laws are so confusing, its all open to to much personal interpretation.

 

[TigerST]

Its much in muchness on the power as you still need incab switch. Unless you plan on hoping out to turn your light on.