wgriswold wrote:
I think we are all in agreement. Wire gauge and length should be sized to the max amperage it will be be expected to carry. The connecting wires between banked batteries will be short and so can be higher gauge and carry the same amps that the longer wires carry from the trailer to the battery. Those of us with OEM electrical systems will do just fine with the short premade connecting wires available from the auto parts store.
Thanks for checking my thinking. All my electrical training came from a physics course many years ago and there was not much real world application so I always check with people who know more than I do.
Not sure as to what you mean about "a higher gauge".
Gauge number goes UP and the WIRE SIZE AND CURRENT CAPACITY GOES DOWN while RESISTANCE GOES UP.
Gauge number goes DOWN and the WIRE SIZE AND CURRENT CAPACITY GOES UP while RESISTANCE GOES DOWN.
IE 10 ga is bigger physically and carries more current and has less resistance than 12 ga.
2 Ga is physically bigger and has more capacity and less resistance than 4 gauge.
While it is true that a very "short" small gauge wire could handle more current, there IS danger in doing this..
#1, higher resistance = more voltage drop (and that IS bad especially with 12V)
#2, Higher resistance = MORE HEAT IN THE WIRE = INSULATION FAILURE = POTENTIAL FIRE HAZARD!
#3, Your very short small ga wire NOW BECOMES A FUSE as in that jumper WILL eventually fail by melting the copper..The cost IS MINIMAL to at least use the SAME wire gauge size as a minimum starting point as the connecting wires from the RV to battery..
Upgrading to a larger interconnect wire (especially when talking the short distance between batteries) is mere Pennies.
Keep in mind that internally inside the batteries they ARE using very heavy Lead "Buss bars" that act as Interconnects between the cells. Only stands to reason that YOUR own external Interconnects should be as robust as possible for best performance of your battery bank.
Otherwise, you might as well just use a bunch of cheap "Ray-o-vac" dry cells in a flashlight to power your RV..
