Magnum Energy MSH3012RV-L Inverter/Charger wiring diagram

This entry is the MSH3012RV-L, the lithium-compatible variant of the 12 V, 120 V / 60 Hz MSH-RV inverter/charger. It remains separate from the original MSH3012RV in saved drawings. The manufacturer's exact -L product page links the July 2026 Rev F installation manual used here.

The inverter supplies 3000 VA / 25 A continuous AC output and the charger supplies 125 A DC. Maximum continuous battery input is 400 A, a worst-case design value at low battery voltage, not typical consumption. The 88% peak inverter efficiency and 36 W no-load consumption describe different operating conditions; neither replaces that 400 A conductor-sizing bound. The 85 A surge figure is AC, so the catalog does not mislabel it as DC surge current.

Tables 2-1 and 2-2, printed pages 14–15, specify 400 A time-delay protection and at least 4/0 AWG / 107.2 mm² per polarity up to 5 ft / 1.524 m one way. Runs from 5 to 10 ft require two 4/0 AWG conductors per polarity; longer runs are not recommended. The example stays within the single-conductor distance limit. Crimp's conservative current and headroom assumptions may select larger conductors.

Select a Class T or equivalent DC protective device with adequate interrupt capacity for the actual battery bank, and verify its time-current characteristic. The schematic's fuse-family label does not verify a particular fuse or the battery fault current. The example AGM bank is a placeholder; replace it with the actual bank and verify discharge capability, charge acceptance, BMS requirements and temperature limits.

HOT 1 IN powers the charger. HOT 2 IN is pass-through only. The two input legs may each transfer up to 50 A. With both connected, they must come from the same source with the phase relationship and common neutral required in the installation manual.

Rev F Table 2-3, printed page 22, permits 60 A on HOT 1 OUT with load support and 50 A on HOT 2 OUT. These are the conductor-rating bounds represented by the terminals. The older October 2020 sellsheet lists 50 A in its charger-mode summary; use the current installation table for the complete wiring configuration. In battery-only mode the two outputs share 25 A total on the same 120 V phase; they cannot supply a 240 V load between them.

Crimp models charging and inverting as separate operating states. It does not simulate hybrid load sharing, the 224 A battery load-support limit, AC phase relationships, neutral switching or output-load allocation. AC branch breakers and protective earth must be designed separately.

Connect the ME-ARC50 to the inverter's green NETWORK RJ11 port using Magnum's four-conductor twisted-pair 6P4C remote cable, not RJ45 Ethernet. MSH-RV §3.13, printed page 45, identifies that port and the firmware-compatibility requirements. Follow its restrictions when choosing remote control versus RV-C control. The signal in the drawing does not carry modeled battery current or simulate remote commands.

Lithium-compatible hardware does not automatically select safe battery settings. The manufacturer's -L product page states that the dedicated LFP preset is available through compatible ME-RC / ME-RVC controls, not the ME-ARC. For an ME-ARC installation, verify supported firmware and configure the battery manufacturer's approved custom charge settings; do not assume an LFP preset, lead-acid equalization or temperature compensation is appropriate.