The comprehensive 123\SmartBMS Victron software operation ensures good battery management. From simple installations to multiple banks and exceptions, it is all possible.
Every connected 123\SmartBMS USB appears as a separate instance in the Victron console. For example, when you have two battery banks – each with their own 123\SmartBMS and USB cable – both instances show up on the Device List in the console.
Besides each BMS instance, an extra instance called “123\SmartBMS Manager” always shows up. This manager takes the BMS values of multiple banks and combines them into one big battery.
Combining multiple battery banks #
It is possible to combine multiple battery banks, as long as the banks have the same amount of cells in series. Each battery bank need it’s own BMS, connected with a USB.
When the Victron has multiple battery banks connected, more specifically multiple banks with different amount of cells in series, then the Manager will use the battery information of the battery with the most cells in series. The Manager excludes all others banks.
Note: the Victron CCGX cannot handle more than 3 connected BMS instances because of its CPU. The Cerbo GX has no problem with more than 3 BMS.
Tip: if the Victron GX does not have enough USB ports, use a USB hub.
Excluding a BMS #
It is simple to manually exclude a BMS. For example, because you only want to monitor a battery bank. The Manager then should not include this battery bank. To exclude a connected battery, give it a name starting with an asterisk (*). You can change the name by going to the Victron (remote) console. Select the 123\SmartBMS instance->Device and select the Name. Change the name to anything starting with an asterisk (*). The Manager will now exclude this battery.
Battery operational limits #
The Manager calculates the battery operational limits (BOL). You can view the calculated limits when you go to 123\SmartBMS Manager->Parameters. BOL contains the following parameters: charge voltage limit (CVL), charge current limit (CCL) and discharge current limit (DCL).
During charging, the software constantly tracks the highest cell voltage. When the highest cell goes a little over the Vfull/Vbalance value, the CVL changes constantly, trying to keep the highest cell voltage below Vmax.
When all managed batteries are full, the algorithm lower the CVL even more. This prolongs the battery life and prevents the BMS from wasting energy during balancing. The next day, the CVL will be back at the original value, so the battery can be fully charged and balanced again with the new day’s solar energy. The CVL will also go back to the original value when a disbalance between the cells is detected of 40mV or more.
The DCL value is based on the SoC. Below a certain SoC value, the algorithm lowers the DCL. The lower the SoC, the lower the DCL. When one of the cells gets close to Vmin, the algorithm will lower the CVL even more, trying to keep the lowest cell above Vmin. The DCL is slowly increased again when the lowest cell is back to an acceptable value.