Tow Vehicle alt/battery is 50 feet from trailer LiFePo. I can run 4 AWG all the way (50’) to Orion. (Then terminate to 6 AWG into Orion). Voltage drop would be ~6%, ~1 volt loss, ~35 watts in wire. Voltage at Orion would still be over minimum needed by Orion. Output run length to LiFePo would be minimal. Am I asking for trouble???
Hi @GuyVic,
If the start battery is 50' from the Orion, then you have a 100' round-trip cable run - remember that you must account for both POS and NEG wire length in a DC circuit.
The Orion will pull an average of ~40A from the start battery to deliver ~30A to the target battery, so 100' @ 40A @ 13.6v = a minimum cable gauge of 1/0 for the main length of the run to just barely squeak by under the 3% maximum allowable vdrop in high-current applications (1/0 would net you 2.97% vdrop at that length). Anything over 3% vdrop on a high-current application is not acceptable.
Long story short, yes, you're asking for trouble.
If I misunderstood you, and the Orion is only 25' from the start battery for a 50' total circuit length, then you should use 2AWG at minimum to keep under 3% vdrop.
The Orion will operate on 10 volts, so I am pondering the relevance of the 3% drop guideline. If the alternator supplies 13.3 volts minimum when engaged by the Orion (it drops the amperage to nil to check actual voltage at the supply end, then kicks back up the amperage to meet charge demand), then a 6% drop would still supply plenty of voltage for the Orion to operate, it would not seem to care. And my understanding of the 3% guideline is to protect equipment on the far end from low voltage, but the Orion is immune to low voltage, it would just shut off. Thus, the concern would be the dissipation of the lost wattage in the 50 foot (100 foot) run of 4AWG, less than 50 watts. You are totally right about the gauge required to meet the 3% guideline, just pondering it’s applicability to this scenario.
Could someone demonstrate what should be the charging :curve in this situation:
Truck batterie - 25 foot of gauge 2 wire with a Anderson connector - Breaker 60Amp - ORION-TR SMART 12/12-30A - 2 foot of gauge 6 - 2 Battleborn 100amp
Batterie SOC at 60% as per BMV-712
ORION-TR SMART 12/12-30A setting as per BattleBorn
i start my truck.....voltage is 13.6
what voltage should i see after the ORION?
what should be the amp?
what is the curve (amp and voltage) to bring the batteries full?
For what its worth I am running 10awg for about 10' and getting roughly 280watt max into my battery system
