I have a five bank 255AH AGM marine battery configuration with four house batteries connected directly to the negative post on the BMV shunt, and one to the main negative buss. The main negative buss is about 25 feet from the four house bank/shunt buss and 20 feet from the fifth battery. The feed from the shunt to the main negative buss is a 4/0 cable and the one to the single battery is a 2.0. I also have a single 410W solar panel running through a VE MPPT 100/50 to control battery charging when no other external charging options are available. Hopefully that explains well enough the basic configuration. I have two questions:
- I have 1020AH (255X4) set up in the BMV battery configuration as there are four batteries directly connected to the battery post of the shunt. I presume that is correct or should I set it up for 1275 because the fifth battery is still part of the system and is being charged by the MPPT or other external sources?
- Depending on the answer to the above, is it worth it to run another 2/0 cable the last 25 feet or so and take the fifth battery off the main negative buss and connect it to the shunt directly? I dont believe the voltage drop in that short a distance with 2/0 is a big factor but does the BMV need to be set up for the total of all five batteries on the circuit?