Dual battery - cable rating?

[bazinoz]

Hi guys.
Just fitting a second battery onto my 92 Patrol.
Main battery is a Marine Pro, the second one will be just a standard car battery as I only intend to run a few accesories off it - never use for emergency start or winching etc.

My question is, what size (rating) cable do I need to run from my main battery to the isolating solenoid & onto the second battery. I take it it doesn't have to be big heavy duty (ie 100amp) cable as it will only be used basically to charge the second battery.

And another quickie - I am making up a 'socket box' to fit in the back via a ELV plug/socket. I will fit a standard ciggy lighter socket and one of those Hella universal types. Are there any other sockets you would recommend fitting while I'm about it. ie Do any car accesories come with other types of connectors?

Thanks in advance for any useful info.

[RoldIT]

8AWG will do the job but depending on the cable lengths, to reduce the voltage drop 4AWG would be more appropriate. The bigger the better when it comes to 12v cabling.

[chimpboy]

8AWG will do the job but depending on the cable lengths, to reduce the voltage drop 4AWG would be more appropriate. The bigger the better when it comes to 12v cabling.

I agree with this... it's not whether it can handle the current, it's whether it can handle the current and not lose much voltage in the meantime.

Having said that the kits usually come with 8AWG aka 7.91mm2, which is what I used. That's only to go across the engine bay though. If you were going to the tray of a ute it could be a longer cable and more voltage drop.

As for the socket box, what you have in mind sounds fine to me; but depending on where you put it what about throwing in a small inverter as well, so you have a 240V socket? There are a few spots inside the walls of the back of the patrol (eg under the jack) where you can squeeze one in. Just a thought.

Jason

[RoldIT]

I used 2AWG for mine and that was just across the engine bay but my vehicle has a 100amp alternator and I also have it setup for emergency jump starting.

Maybe a little overkill but was cheap and fairly easy to work with and as I said the more you go with 12v the better.

[bazinoz]

Thanks for the replies guys. Sounds like 8awg will be the go.

As for the 240v invertor idea, what sort of current does that draw through the 12v cabling? Could you run a 240v bar-fridge? Or would it be limited to just the missus hair dryer

[HotFourOk]

Hey.. hair dryers take heaps of power!

Depends on the size of the inverter.. better off getting a 12V fridge if you need to use one
It could run things like a playstation