size of cable does it matter

[turbojoe]

size of cable does it matter. ? i am running from aux batt to rear of patrol for hook up to camper .Using anderson plug of course. 6mm or 8mm ,this is the question.

[Muckinhell]

well that depends if you are going to run a dc-dc charger in the camper. if you are running a dc-dc then 6mm should be fine but if not then best size would be 6B&S cable to limit voltage drop.

[winniliss]

size of cable does it matter. ? i am running from aux batt to rear of patrol for hook up to camper .Using anderson plug of course. 6mm or 8mm ,this is the question.

YES

16mm2 cable is the better option in the long run. Refer to the following link (as an example) at the bottom of the page. The lengths are for twin core.

http://www.solarhome.ru/en/basics/batteries/sizing_cables.htm

If you want to supply 4 amps from your main battery to run your fridge using 10mm2 twin core cable you could do this over 17 meters.
Now you want to charge your aux battery also you would want around 20 amps, 16 amps to charge the battery and 4 amps to run the fridge but you can only do this over 3.5 meters. Using longer cable lengths and you start getting voltage drops. In turn your battery takes longer to charge. Your battery isolator might not work properly if it's electronic also. At 16mm2 twin cable you can do this over 5.5 meters.

With DC to DC chargers they require more current on the input (from main battery) i.e. 25 amps to supply up to 20 amps on the output (to the aux battery) so this would make the matter worse. You have no free lunch with these devices.

For example a 12vdc to 240vac 600 watt inverter will suck up to 50 amps from your battery (watts divided by volts = amps). You can only do this over 2.2 meters using 16mm2 twin core cable. You could in theory nearly double the length if you use the chassis or body of the vehicle as an earth but your connections have to be spot on and not degrade over time being exposed to the elements.

I hope this helps. Most common electrical issues are related to under size cables and or bad connections. Worst case it will take a lot longer to charge your aux battery and a few hours of driving during the day will not top the battery up.

Winston.

[SteveandViv]

YES

16mm2 cable is the better option in the long run. Refer to the following link (as an example) at the bottom of the page. The lengths are for twin core.

http://www.solarhome.ru/en/basics/batteries/sizing_cables.htm

If you want to supply 4 amps from your main battery to run your fridge using 10mm2 twin core cable you could do this over 17 meters.
Now you want to charge your aux battery also you would want around 20 amps, 16 amps to charge the battery and 4 amps to run the fridge but you can only do this over 3.5 meters. Using longer cable lengths and you start getting voltage drops. In turn your battery takes longer to charge. Your battery isolator might not work properly if it's electronic also. At 16mm2 twin cable you can do this over 5.5 meters.

With DC to DC chargers they require more current on the input (from main battery) i.e. 25 amps to supply up to 20 amps on the output (to the aux battery) so this would make the matter worse. You have no free lunch with these devices.

For example a 12vdc to 240vac 600 watt inverter will suck up to 50 amps from your battery (watts divided by volts = amps). You can only do this over 2.2 meters using 16mm2 twin core cable. You could in theory nearly double the length if you use the chassis or body of the vehicle as an earth but your connections have to be spot on and not degrade over time being exposed to the elements.

I hope this helps. Most common electrical issues are related to under size cables and or bad connections. Worst case it will take a lot longer to charge your aux battery and a few hours of driving during the day will not top the battery up.

Winston.

Good post and

You have no free lunch with these devices.

So true.

[sablesoft]

YES

16mm2 cable is the better option in the long run. Refer to the following link (as an example) at the bottom of the page. The lengths are for twin core.
...

Winston.

Hi winniliss,

    x2
16mm2 cable is the way to go, with most cars this will allow direct charging without the need for a expensive 12V-12V charger, and if there is a need to use a 12V-12V charger is is still better to use 16mm2 Cable, voltage drop is power wastage.

Ray

[sablesoft]

I hope this helps. Most common electrical issues are related to under size cables and or bad connections.
Winston.

X2

[Marcus73]

size of cable does it matter. ? i am running from aux batt to rear of patrol for hook up to camper .Using anderson plug of course. 6mm or 8mm ,this is the question.

A question like that is just asking for trouble


Sent from the machine that goes..... Bing!

[Symon]

well that depends if you are going to run a dc-dc charger in the camper. if you are running a dc-dc then 6mm should be fine but if not then best size would be 6B&S cable to limit voltage drop.

As has been said by others, even with a DC-DC device you still need the heavy cable.

[sablesoft]

As has been said by others, even with a DC-DC device you still need the heavy cable.

X2

[turbojoe]

Thanks for all the advice guys , very informative , went with the 6b s cable for the 5m run
To the camper.