I am moving from a Lead Acid house battery bank to a Freedom Won 20/14 Marine LiFePO4 battery.
In the existing system design there are Main DC buss +Ve and –Ve .
All users and chargers are connected to the main DC buss.
Users & chargers connected to main DC buss;
- 2 x 20 year old Phoenix MultiPlus 24/3000/70 18series firmware
- Charging parameters will be set by LED’s and press buttons.
- MPPT 100/50 (supplying DC buss)– communication connected directly to CCGX via VE. Direct cable. (This could be the only piece of equipment which is recording Dc current input outside of the the Freedom Shunt)
- 3 Alternators producing a combined 240Ah. This is a de-rated setting.
- Main DC Panel – from which DC is distributed.
“Here is an excerpt from latest CCGX manual. 2019-07-29
The three products that calculate SOC are:
1. Battery Monitors, such as the BMVs, the Lynx Shunt, or the Lynx Ion BMS
2. Multi and Quattro inverter/chargers
3. Batteries with built-in battery monitor and a (mostly CAN bus) connection to the CCGX.
When to use what?
If you have a battery with build-in battery monitor, such as a BYD or Freedomwon battery; it’s easy. Use that.
If the MultiPlus or Quattro inverter/charger is the only source of charge to the batteries and the only draw then it can function as a basic battery monitor because it counts what went in and counts what comes out. No need for a dedicated battery such as the BMV.
If the systems consists of an inverter/charger, MPPTs and a Venus-device, then there is still no need to add a dedicated battery monitor.
For any other system types, such as a boat or vehicle with DC lights and other loads, a dedicated battery monitor will be required.
2.4.2 The different solutions explained in detail
(C) Batteries with a built-in battery monitor
In cases where the system includes a battery which has a built-in battery monitor and SOC calculation - such as many of the batteries listed here - a dedicated battery monitor is not required.
1. Connect the battery communications cable to the CCGX according to the instructions.
2. In the CCGX, in Settings → System setup, verify that the selected Battery Monitor is the battery.
Note that the Battery Monitor setting in VEConfigure3 is irrelevant. For systems like this, changing this setting will have no effect on the charge or any other parameters in this type of system.
(D) Other system types
When there are more chargers, or loads, connected to the battery than just the Multi or MPPT Solar Chargers, a dedicated Battery Monitor will be required.
House loads in Marine or Vehicle system.
PWM Solar Chargers
AC chargers, such as Skylla-is, Phoenix chargers, non Victron chargers, etc. Old Victron Pheonix Multi’s, Alternators
1. Configure all BMV parameters (see BMV documentation)
2. In the CCGX, in Settings → System setup, verify the selected Battery Monitor. It should be the BMV Battery Monitor.
Note that the Battery Monitor setting in VEConfigure3 is irrelevant. For systems like this, changing this setting will have no effect on the charge - or any other parameters - in this type of system.
Note that this is all about showing an accurate state of charge to the user, rather than being required for an efficient system. The SOC percentage is not used for battery charging. It is, however, required when a generator needs to be started and stopped automatically based on battery SOC.
For hub-2 installations we recommend you do not add a BMV to the system as it will only
confuse the user when there are two SOCs with different readings being displayed.”
The above statement is a little confusing.
Surely the Freedom Won internal shunt will see all incoming and outgoing current to its cells as it is connected directly to the main DC busses. Therefore no need for a BMV 700 series??????
The net current and SOC should be indicated by the CCGX – CAN bus connected to the Freedom Won.
Freedom Won BMS is controlling the MPPT only, via the CCGX.
MPPT 100/50 (supplying DC buss)– communication connected directly to CCGX via VE. Direct cable. (This is be the only piece of equipment which is recording Dc current input on the CCGX as well as through the Freedom). Indicating the current input on the CCGX as well as through the battery BMS could give a false SOC???????
Is the above statement correct and is this the reason a BMV 700 series is required when other charging sources are present. Therefore the BMV will become the primary source of SOC. Even though there is an internal shunt on the battery BMS>
Thanks for feed back in advance.
@mvader, @ Guy Stewart