Victron MultiPlus-II 12/3000 2x120V connections

The MultiPlus-II 12/3000/120-50 2x120 V accepts North American 120/240 V split-phase or a single 120 V supply. It has a 12 V battery connection, 120 A charger, and 50 A AC input limit per leg. Its 3000 VA inverter supplies 2400 W continuously at 25°C, shared across the supplied loads.

The operating explanation, printed page 3 is essential: with split-phase shore power, the outputs follow the input phases. During inverter operation, L1 and L2 are joined and both carry the same 120 V phase. There is no 240 V between them. A 240 V appliance therefore requires a suitable external split-phase supply; two output legs do not double inverter power.

Crimp's AC IN L1 / L2 / N and AC OUT L1 / L2 / N map to the main input and backed-up output. DC + / DC − connect the battery and carry current in both directions. Protective earth, chassis grounding, the mains-only AC-out-2, VE.Bus, sensors, and controls are absent from the symbol.

The charger and PowerAssist operate on L1. The adjustable input-current limit controls L1 rather than protecting an overloaded L2. Size and protect each AC circuit using the actual source and load arrangement.

The battery table, printed page 12 specifies a 400 A DC fuse, two AWG 1/0 cables per polarity for 0–5 m, or two AWG 2/0 per polarity for 5–10 m. The table assumes 90°C copper and excludes closed-conduit installation. M8 battery-stud maximum torque is 12 N·m. Verify parallel-cable installation and the battery/BMS discharge and charging capabilities separately.

The AC table gives 50 A input, 75 A main output, and 50 A auxiliary output protection ceilings, with AWG 6 minimum under its stated conditions. The actual upstream supply can require smaller protection and a lower configured input limit. Main-output protection must account for PowerAssist.

The internal ground relay connects output neutral to chassis when inverting and opens before external AC connects. Preserve the protective-earth path and required residual-current protection; the canvas does not validate grounding or split-phase operation.

Mount in a dry, ventilated position and follow the manual's clearance and cable requirements. Set battery chemistry, charge current, the shore-current limit, and the battery's approved BMS controls. Test loss and restoration of shore power with the intended loads, including that 240 V loads stop when inverter-only operation begins.