7 Pin plug wiring?

[SteveP]

I have the two 7 pin wiring on the car & van, Black & Grey.

Question is; to enable me to charge a spare leisure battery whist we are driving around (without van in tow!) I have bought a Grey Plug & cable, so i can connect the appropriate wires to the Pos+ & Neg- on the battery, using crocodile clips,

Which coloured wires onto which terminals on the plug?

 

[colin-yorkshire]

hi steve

personally I dont understand why you want to it this particular way?? but the answer is blue and white blue being the charge wire and white the earth.

 

[marlot]

If you're going to do this, you'd be much better off getting some quick release battery clamps. Crocodile clips some off too easily in a moving vehicle and could cause some interesting sparks - especially if the boot if full of hydrogen from the battery having been on charge.

I'd also recommend strapping the battery down in a battery box.

 

[SteveP]

Colin, to answer your question, i want to be able to charge an extra battery, for when rallying, so when 1 runs out the other is ready, also to charge the dead battery, whilst we are running around (without van) doing day trips, run outs etc

 

[colin-yorkshire]

hi steve

figured it was for something like that I had a similar system fitted to the m'home but used the van wiring instead.

timothy's suggestion of using quick release clamps and and a battery box is a good one. the white wire from the plug is a common earth that comes from the car boot anyway so adding an extra wire to it is no trouble, the blue wire feeds the charging circuit from a smart relay again adding an extra wire from the relay to the spare battery is no big job' so all the wires would be within the boot (no need for and external 7 core wire going from the plug to inside the boot) furthermore if you added a 2nd smart relay just to feed the spare battery it could be left in the boot charging up while the van was being towed as the grey plug is now free.

hope this helps

colin

 

[SteveP]

hi steve

figured it was for something like that I had a similar system fitted to the m'home but used the van wiring instead.

timothy's suggestion of using quick release clamps and and a battery box is a good one. the white wire from the plug is a common earth that comes from the car boot anyway so adding an extra wire to it is no trouble, the blue wire feeds the charging circuit from a smart relay again adding an extra wire from the relay to the spare battery is no big job' so all the wires would be within the boot (no need for and external 7 core wire going from the plug to inside the boot) furthermore if you added a 2nd smart relay just to feed the spare battery it could be left in the boot charging up while the van was being towed as the grey plug is now free.

hope this helps

colin

Cheers Colin, yes i understand what you are saying, i need to find the relay (somewhere in the boot) and run the blue & white wires from there?

I have the battery box, also point taken i shall use clamps instead of clips!

Query? Do i need second split relay?

regards

Steve

 

[colin-yorkshire]

hi steve

only the blue wire comes from the smart relay the white earth wire will be attached to the metal boot panel somewhere usually secured by a bolt or self tapper there will be two white wires one for each plug (the black lights plug is also earthed) it should not be nessasary to use an extra relay UNLESS you intend to charge the spare battery while towing, in which case it may be prudent to fit one.

oh and I nearly forgot, don't forget to fit a 15amp inline fuse between relay and spare battery in case of problems, the smart relay feed wire will allready be protected by a 20/25amp fuse so if there was a problem the 15amp fuse would blow first.

colin

 

[SteveP]

Thanks Colin, you are a gent!

 

[WatsonJohnG]

The battery clamps on my caravan have velcro on the back so that when the van is being used without a battery in situ they ar velcroed together back to back to avoid shorting

I would prefer in a car boot to put the live lead in something like a mobile phone case to avoid contact with the car bdy earth

I used to use plastic bread bins as cheap battery boxes when I charged up a battery in the boot

 

[SteveP]

Thanks Gents,

Job done, took blue feed from smart relay for+, Black on relay for - and fitted 15 amp in line fuse, also the idea of velcro back to back; Jobs a gud un! 13. 8 charge going to battery when engine starts.

 

[colin-yorkshire]

Thanks Gents,

Job done, took blue feed from smart relay for+, Black on relay for - and fitted 15 amp in line fuse, also the idea of velcro back to back; Jobs a gud un! 13. 8 charge going to battery when engine starts.

hi steve, nice one glad to be of help

 

[Gafferbill]

Safety issues....

Battery should not be charged in passenger compartment of car unless it is a sealed gel type.

Car boots are not usually separate in terms of ventilation from the passenger area.

Lead/ acid batteries give off hydrogen when being charged... an explosive gas.

Battery has to be physically restrained from any movement in case there is an accident.

Advisable to have safety notice near main car battery informing Fire/ Rescue service that a second battery is fitted.. They disconnect batteries at the scene of an accident as a priority

I am not being a killjoy.

I myself have fitted a second battery system on my towcar, which addresses all of the above.

It works well and connects to the caravan when on site with a 3 meter S extension lead.

 

[hgv dave]

hi steve

just a thought....how about trying a solar panel battery charger?,it would save a lot of messing around.

hgv dave

 

[DeliDave]

Have just bought a heavy duty battery pack from costco for the same thing,it has compressor and light,2 12volt outlets and USB outlet,designed for large engines and loads stronger than the Maplin one i have as well.It can be charged from a lighter point in car or off mains.Got it to use at Malvern show next week as going Thurs to Sun and would like to watch TV a little.It is also sealed so no damage if it falls over.