42' sailboat LFP upgrade

My 42" sailboat had to get new batteries. I wanted to upgrade the system with inverter, watermaker and allow for solar and engine alternator to provide all energy needs without connection to the shore.

This is the new electrical diagram:

Due to space limitations, the battery compartment was used for 550Ah of ELERIX batteries, REC Active BMS, main fuse and battery disconnect, as well as two Orion-Tr 18A chargers for engine and bowthruster battery.

MultiPlus Compact 1600VA was just small enough to replace old 220V charger in the “energy compartment” with MPPT and Cerbo GX.

For the alternator I have used Nordkyn VRC-200 regulator which allows me to use my stock Mitsubishi 115A alternator and charge LFP with up to 100A safely.

REC Active BMS is connected to Cerbo GX via BMS-CAN and controls MultiPlus and MPPT charging via DVCC. Alternator charging is controlled also by BMS via charge enable signal and I can turn off alternator charging via Cerbo relay.
Orion chargers are constantly maintaining engine and bowthruster lead-acid batteries from LFP and are also controlled via Cerbo GX relay.

I am very happy with new system as it provides us with enough energy for longer stays away from shore power. I am currently 8 weeks away from shore power and have all the energy needed and we are producing all our water for the needs of 5 people.

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