Electrical
1Overview
A 12V Victron system sized for extended off-grid living. An 810Ah LiFePO4 bank charged by dual-MPPT solar, with 120V through a 3000W inverter. Coastal salt air and washboard vibration shape the hardware and finish choices throughout.
2Battery bank
3Charging
Two MPPT charge controllers, currently non-networked, so each runs its own charge algorithm off its own terminal voltage reading. That works but is suboptimal.
Improvement identified, not yet done: enable VE.Smart Networking using the already-installed SmartShunt as a shared voltage reference, so the two controllers synchronize their charge stages.
4Inverter & AC
A GFCI main causes nuisance trips in humid coastal air, so GFCI protection lives at the individual wet-location outlets instead of the feed.
Separate breakers, each sized to its wire gauge:
- Cruise N Comfort mini-split
- Isotemp water heater 120V element
- Other loads
5Distribution & grounding
- Victron Lynx Distributor for DC distribution.
- SmartShunt on the bank for state monitoring, and the shared reference for the planned VE.Smart network.
The Unicell composite box is not bonded to the chassis, so there is no inherent ground path. System negative references a single chassis grounding point on a heavy gauge run (2 to 4 AWG). Final ground location, floor penetration to frame vs. a longer run to the cab, is still open.
6Decision log
GFCI placed at wet-location outlets, plain 30A at the main feed, to avoid coastal nuisance trips.
VE.Smart Networking chosen as the fix for unsynchronized dual MPPTs, using the existing SmartShunt as the voltage reference.
7Open questions
- Roll out VE.Smart Networking to sync the two MPPTs (identified, not yet done).
- Alternator DC-DC: 2 vs. 3 Orion XS units.
- Final ground location: frame penetration vs. cab run.
- Shore power inlet: SmartPlug vs. Marinco.