Power to fridge

G'day Rock Crawler, use 6mm wire and earth it all locally ie closer to the fridge.

Hi there,

Derek here...

I agree, I use 6mm wire for fridge only applications but if you plan on running an inverter in the rear then best to run a 8mm2 100amp positive to the rear and pick up a good clean earth around the tail light area.

I would also reccomend a auto reset breaker at the front and a buss bar or heavy duty fuse block at the rear before spliting to the fridge and inverter.

Regards Derek.

Merry Christmas to all and Happy Holidays.

Ran mine back to battery
if ya going to run a power wire most of the length, may as well run the earth too...

Eric, i would prefer to take it right back to the battery as you never know if there may ba dodgy connection to the earth one end or the other.

Glad you preface the question with the "not so tuf 100". ;-) A 90 litre should feed you and Dean a couple of days mate. Nearly do a double crossing of the Simpson with it. Have a great Christmas for you all, Giota and kids too.

I would run the earth back to the battery. After all it is no harder to run a twin than a single and after all you are trying to connect the fridge to the negative of the battery not the body of the car. Read the instructions with the fridge for the correct size cable. I went one size bigger as it can do no harm as you may also run other gear off the same cable. I changed the cigarette lighter connector for a different style to be sure it doesn't fall out on rough roads. Didn't want to risk warm beer at beeroclock.

Best practice as Waeco recomends is twin core 8mm sq pos and neg to battery ,the last thing you want is hot beer because of a coulpe of $ "saved " on to thin wire causing volt drop .

The negative lead should never be connected to the battery terminal but rather the body end of the negative battery lead.
I used to install HF radios in all sorts of vehicles, trucks, buses, 4wd's and cars.
The reason is that if (it does happen I've seen the results) the battery connection is crook/broken the huge current required by the starter motor will take the path of least resistance, through the frig, HF or whatever. Believe me the HF, frig or whatever will NEVER work again.

Connecting the neg to the body at the rear is fine, and actually provides a path of least resistance provided (#1) you strip off the paint, smear some vaseline to stop it rusting and use a shiny bolt and (#2) have an excellent earth lead between the battery and body.

The reason the fridge people suggest to go back to the battery is because people easily stuff up an earth connection to painted surfaces in the vehicle. I solder a 30amp spade fuse in line at the battery end for short circuit protection. I have found that fuse holders can corrode up under the bonnet, and a soldered fuse has the least resistance.

RC . Try a search. This topic is covered every week & the responses are all pretty much the same ;-) Heres my last response from 3 pages back.
I suggest running twin double insulated 6mm cable (or bigger) from the auxillary battery through a waterproof 30 amp spade fuse holder connected directly to the terminal. Keep the wiring as short as possible to minimise voltage drop. Ideally this could connect into a heavy duty power outlet then be looped out & run to a 2nd plug for the lights. (4mm would be ok for lights)(clipsal 32 volt plugs are excellent). Avoid cigarette lighter type plugs as they vibrate out & often melt.
Running the earth wire from the battery eliminates poor connections through the body work particually over time when things start to rust.
The fuse at the battery should be no larger than what your load usage requires enuring that if the positive wire was to rub through onto the body it will blow & not set fire to the wiring. A 20 amp fuse should carry the load fine.

On my own 4by I've taken it one step further by running 16mm twin cable from the battery in through the cab then out to the rear bumper into an Anderson plug. This is either an external power point for assesories or power into the caravan. I've then tee'd off the main cable at various points for power to the CB's, HF, fridge, light plugs, compressor, GPS, shower & diff locks. Individual spade fusing of the appropiate size is fitted where I tee off. This system minimises voltage drop & mutliple runs of wire along the car.
Cheers Craig.........