12 Source and Earth

[TyeBoi]

I am looking for a decent, easy to reach 12v source in my puma.

I have some custom lights which need a 12v input and a an earth. They recommended using the cig lighter wires but after I wasted about an hour trying to fiddle with them i decided it wasnt worth it.

Does anybody know of a good 12v live source around the dash area within easy reach so I can piggy back my lights to it and then earth it some where too?

Btw the lights have there own switch..

And for the moment i have cut a cig lighter adapter plug off a phone charger and used that as my 12v source and earth which works fine but looks stupid and is very impractical.

 

[Dal]

I would have used the cig lighter wiring as it's fairly chunky as there is quite a bit of current going down there when in use so should be ok for some lights.

Failing that, take a fresh (fused) point straight off the battery, through the bulkhead grommit and terminate it wherever you like up behind the dash.

 

[TyeBoi]

yeh i was going to do the second one actually... into some kind of chocolate box or something that i could link a few lights up to.... any ideas on what kind of wire to go for and what fuse ?

 

[Dal]

Depends entirely on the the load (current) that the lights will draw.

Have a look here and especially at section 14 : fuses.

http://www.bcae1.com/" onclick="window.open(this.href);return false;

 

[TyeBoi]

hmmm ok

so far this is what I have come up with



12V battery output ----> Fuse ------->||(grommet)--------->Distribution box------> x2 (2 seperate outputs with fuses attacked)----------> straight to the inverter which requires a 12v input and inverts to 3v which then goes to the cold cathode neons.


All i need to do now is work out the wire guage and fuses that I need.

 

[Dal]

How many watts in total will you be pulling with the cathode neons?

Then multiply divide that by 14.4v (Max-ish car voltage) 12v to give the theoretical maximum current (amps) that you'll need. Then see that website I referenced to see what gauge (AWG) wire you'll need and the fuse to go with it.

I doubt it'll be more than a few amps so it'll not be that heavy gauge as a guess.

 

[comfortablynumb]

Shouldn't that be divide by 14.4v, Power = volts * current
Safer to divide by12 as battery and alternator voltage will fall when under load (e.g. headlights on, screen heaters on etc etc)

 

[Dal]

Divide yes.. Darn my old confused brain!

Ta CN

 

[TyeBoi]

lol

Thanks for the great responces..

I think the the cold cathode neons require 12v per inverter. and I have 2 inverters powering 2 seperate neons.

I also have undercar neons that I am considering putting on my puma... they require a 12v input

not sure on the current. will it say on the side of the box u reckon? I will have to go have a look.

 

[Dal]

It may. If it says 48 Watts for example then it'll be 4 amps.

48 (watts) / 12 (volts) = 4 amps

 

[TyeBoi]

lol thanks for you help on this Dal..

I havn't had chance to have a look at that website properly yet but I have scanned a few bits..

just a little idea... I have tested each of the neons using a cig lighter end and plugged it in to the cig lighter socket and attached the wires to the neons. they work fine with no probs... do you think If i found out what fuse goes in a cig lighter i could use a separate one for each of the neons before they got attached to the distribution box and then the distribution box would be attached to my direct (fused) feed to the battery?

 

[comfortablynumb]

Probably not a good strategy, you could end up with a fuse that is too big for the job and not be adequately protected against a fault in the neons.
You can pick up a multimeter for 6.99 at Maplin http://www.maplin.co.uk/Module.aspx?ModuleNo=37279" onclick="window.open(this.href);return false;. You could then measure the current drawn by the neons and be sure of your fuse rating.

 

[TyeBoi]

yes! i didnt think of that.

I have one at home somewhere. I will dig it out

/thanks

 

[TyeBoi]

Ok so yesterday I installed one set of my neons in the boot because I have yet to check the current for the footwell ones and the under car ones so I thought instead i would just install my last set into the boot and attach it to the boot light wires...

worked fine... off when closed and on when open... started the car and a massive wiring noise comes from the alternator and the battery light stayed on. Rang my mate and he said unplug it again and try again so I did and it worked....

great I thought.. cant even do that... this puma is turning out to be a bit of a pain in the arse with its electrics where as the KA used to let you do whatever you wanted to and it would still work no probs...

so now im back to the fact I need a straight 12v source from the battery to some kind of distribution box which splits it at least 3 ways and then they can goto each of the neons which require the 12v source and they can be earthed accordingly....

obvious there needs to be some kind of fusing along the way...

anybody know of a distribution box? something like a multi-plug(for your house)

or can i just split the wire into 3 different bits and put that into a mounted fuse box holding a fuse for each of the neons...

im going to go back to using cig lights in a min i swear lol

 

[martinthrapston]

why not use a distribution box as with amp installs ???

 

[TyeBoi]

yeh i am looking for something like that but i don't know what to look for.. ?

 

[martinthrapston]

halfrauds sell them and so should a decent car parts shop

 

[TyeBoi]

got a link martin? or a picture

 

[martinthrapston]

http://www.halfords.com/webapp/wcs/stor" onclick="window.open(this.href);return false; ... yId_165626

 

[Dogsbody]

I picked up a 4 way one for my Wife's Honda Goldwing.
I want to rewire the cruising lights :-D
http://www.merlinmotorsport.co.uk/ELECTRICAL-Fuse-Boxes/c40_113/index.html

£4 odd last week,
Watts = I x v
and transpose to I (amps) = watts divided by volts which in a car are 12 or near as !!

I took my supply for the amp in my boot direct from the axillary on the key switch, through a 30 amp fuse to the boot. You can pick up a earth from anywhere really.