I have a Multiplus 12/3000/120V, a SMART MPPT 150/100, 1400 W of solar panels, a CCGX and 6 Battleborn 100AH lithium batteries – no battery monitor. In the CCGX settings I have set the Battery Monitor to “Multiplus”. I also have “Use solar charger current to improve VE.Bus SOC” enabled. My 2 questions: The CCGX always shows 99% as SOC. Why? Do I have to set the size of the battery bank (600AH) somewhere in the settings, or how does the system know the capacity of the battery bank?
You set the size of the battery bank in VE.Configure for the Multiplus.
I went through all the tabs in the VE.Confgure but there is nothing where you could enter the total battery capacity
If you have direct 12v draw from the batteries that supplies power to 12v accessories then you will need a BMV in the system to measure current flowing out of the batteries.
Because the voltage curve of lithium is relatively flat, it cannot be used in a reliable fashion to determine SOC. Therefore you need to use a BMV shunt to measure 12v amp hour discharge from the batteries, and report back to the CCGX accordingly using a VE Direct cable for communication.
The MultiPlus nor the MPPT controller will see battery energy flow directly from the batteries to 12v accessories, so they will not be able to report on amp hour usage / draw down in an accurate manner.
Just a thought. Now if your only power draw from the batteries is via the Multi for 120v power through the inverter function, then the Multi should be able to keep track of the SOC.
