[droverdave]

Yes i know 9% is alot, i was more saying that we are still within the required voltage (9-36 or whatever) for the light with the 2.5mm^2 wire, and yer due to the regulator/switchmode inside the LED it can deal with it.

also keep in mind i used 6m of wire in the calc (which is alot of wire!), if you were to mount the light thing on the bull bar, you might get away with 1m or less of wire from the battery to the light, and then the light to earth. that would bring your voltage drop of the 2.5mm^2 down to ~0.17V and for 4mm^2 down to ~0.1V, not much in it.

But yes if your standing in the shop in front of both 2.5mm and 4mm, just grab the 4mm if its only a few bucks more. but if you already have the 2.5mm then she'll be right for this application.

[Blakey]

another note being is can that 2.5mm handle the current draw of the LED light. the volts may be alright but if the cable can't handle the current they you're just going to get a fire when the cable burns out.

[Critical Energy]

Fuck me there's a lot of scientists on here.
ALL the above calculations and opinions are flawed in one way or another, far too much to go into why each one is wrong and the OP doesn't need me swinging my dick about adding more over complicated calculations so I can prove to myself what a good engineer I am.

Top and bottom of it is that you need to buy the correct product for the job, if you don't want to make the loom yourself then spend the money and get a good one

Rich

[Critical Energy]

By the way, I wasn't having a go at anyone there.

[droverdave]

So you why are they flawed?

All very well to say why you think we're wrong, but giving no alterantive doesn't really help.

[Blakey]

i do agree do say why you are so much better than the rest

[Reubs]

droverdave wrote:

All very well to say why you think we're wrong, but giving no alterantive doesn't really help.

Reubs wrote:

If you want an off-the-shelf loom go look at a Piranha DL1 loom or similar...

[Critical Energy]

Fuck I hate it when I wake up cranky.

Not saying I'm any better than the rest, just saying the info is over the top and not accurate anyway.
AS:3008/2009 isn't applicable as it deals with LV AC cabling only.
2.5mm, 4mm, 6mm aren't a cable size associated with automotive cabling.
I also used the metric cable sizes as that's what I'm used to but I shouldn't have.

What I'm getting at is that the poor bugger asked a question in the first place and ended up with a science lesson he didn't need and isn't actually true

[droverdave]

Hmm i didnt realise it was only for AC.

What is the equiveling low voltage DC cabling standard?

[Ausuki]

i normally use this,

[Blakey]

try something a bit larger that tiny pic cant be seen

[Ausuki]

Blakey wrote:

try something a bit larger that tiny pic cant be seen

fixed

[royce]

Critical Energy wrote:

2.5mm, 4mm, 6mm aren't a cable size associated with automotive cabling.
I also used the metric cable sizes as that's what I'm used to but I shouldn't have.

What I'm getting at is that the poor bugger asked a question in the first place and ended up with a science lesson he didn't need and isn't actually true

Every roll of Automotive cable I have in my garage has a proper mm2 size on it, even the supercheap branded little spool I use to pull strands out of

He asked a question and got a few people offering advice they should keep to themselves, some advice of nah use the smaller stuff youll be right and then it seems the people that have been stuffing around with cars forever have all said no go thicker, funny that isn't it

[Blakey]

Critical Energy wrote:

Fuck I hate it when I wake up cranky.

Not saying I'm any better than the rest, just saying the info is over the top and not accurate anyway.
AS:3008/2009 isn't applicable as it deals with LV AC cabling only.
2.5mm, 4mm, 6mm aren't a cable size associated with automotive cabling.
I also used the metric cable sizes as that's what I'm used to but I shouldn't have.

What I'm getting at is that the poor bugger asked a question in the first place and ended up with a science lesson he didn't need and isn't actually true

well if you want to be technical DC cabling would be rated at less current per cable size then AC as every half cycle AC is at 0V and 0A where as DC is constant.

yes your right automotive cable doesn't regularly use cable in sizes of 2.5mm, sq 4mm sq, etc. but they use equivalent sizes in AWG/Ga or B&S so just using mm sq is easier to understand for everyone not to mention most automotive cable is now moving to sq mm sizes anyway.

Under AS3000 and AS3008 both AC and DC low voltage is covered

but because automotive is really Extra low voltage i don't believe there is any sort of electrical standards for automotive ELV DC cabling or circuits.

i would still use something like 3008 to give me my Current carrying capacity. or at least give me a pretty good idea of it. id rather have to large a cable then my vehicle burning down and putting your life at risk.

[Critical Energy]

i would still use something like 3008 to give me my Current carrying capacity. or at least give me a pretty good idea of it. id rather have to large a cable then my vehicle burning down and putting your life at risk.[/quote]

Agreed, it's a good start with readily available figures, and I didn't want to piss anyone off or come across as a dickhead (although I've succeeded).
Upsizing cables in cars is often a good idea as the larger cables are more resilient, as in they are less flexible so don't get damaged as easily through vibrations etc moving them around, especially inside headliners, but electrically it's pointless.

Peace out

[atari4x4]

poor kid just wanted to wire up a light bar

[jake84]

atari4x4 wrote:

poor kid just wanted to wire up a light bar