Victron Energy Battery Balancer

Product detailed description

Victron Energy Battery Balancer
The lifespan of a battery bank can be significantly shortened by charging imbalance between individual batteries. This is a situation where you have 12 V batteries connected in series or series-parallel (not just parallel!). In such a system, one 12 V battery with a slightly higher internal resistance can cause undercharging of parallel-connected batteries and overcharging of series-connected batteries. New battery cells or entire batteries connected in series have almost identical initial characteristics. Their small differences even out during the absorption or equalization charging phase. However, large differences can lead to excessive gassing caused by overcharging of more charged batteries and unwanted sulfation of less charged batteries caused by insufficient charging.
The solution is balanced charging using a battery balancer. It equalizes the state of charge of two series-connected 12 V batteries or several parallel strings of series-connected batteries. As soon as the charging voltage in a 24 V system rises above 27.3 V, the battery balancer activates and compares the voltage of the two series-connected batteries. The balancer can redirect a current of up to 0.7 A from one battery (or parallel-connected batteries) with a higher voltage to the other battery. The result of the different charging current is a mutually equal final state of charge of all batteries.
Battery balancers can also be connected in parallel for more complex systems. In a 48 V system, a total of three balancers are used (see diagrams).
Explanation of LED indicators:
Green LED: device is active and the measured voltage is higher than 27.3 V
Upper orange LED: voltage deviation is greater than 0.1 V
Lower orange LED: voltage deviation is greater than 0.1 V
Red LED: alarm triggers if the difference between the monitored batteries is greater than 0.2 V. The alarm persists until the difference is lower than 0.14 V or the system voltage drops below 26.6 V
Meaning of the alarm relay
In standard state it is open (inactive). It closes (activates) when the red LED lights up, i.e. when the voltage difference between the batteries is greater than 0.2 V. As soon as the red LED goes off, the relay opens (deactivates) again (the voltage difference between the batteries drops below 0.14 V).
Alarm reset
The alarm is switched off by interconnecting the outputs marked as RESET. This can be done using a switch.
Installation
1) The battery balancer(s) must be installed on a well-ventilated vertical surface near the batteries (but not directly above them, due to the possible influence of gases from the batteries!)
2) If required, install the alarm contact wiring and the reset wiring.
3) Use a cable with a minimum cross-section of 0.75 mm2 to connect the negative, positive and middle pole (in this order!)
The balancer is ready for operation. If the voltage on any of the monitored batteries (strings) rises above 27.3 V (during charging), the green LED lights up, indicating that the balancer is activated. If, in this situation, the deviation between the batteries (strings) is greater than 50 mV, active balancing begins, i.e. compensation of the difference between the batteries (strings). If the deviation reaches 100 mV, one of the orange LEDs activates. A deviation greater than 200 mV triggers the alarm relay.
For series-parallel battery arrangements, the middle interconnecting wiring between the parallel strings must be dimensioned to handle the relevant current if part of the battery is disconnected.
Product parameters
Input voltage range: up to 18 V per battery, 36 V total
Voltage level for balancer activation: 27.3 V ± 1%
Voltage level for balancer deactivation: 26.6 V ± 1%
Power consumption in deactivated state: 0.7 mA
Power consumption in activated state: 50 mV
Maximum balancing current: 0.7 A at a deviation of 100 mV and more
Voltage deviation for alarm activation: 200 mV
Voltage deviation for alarm deactivation: 140 mV
Alarm relay: 60V / 1 A, normally open
Method of turning off the alarm relay: interconnecting the two outputs marked as RESET
Overheating protection: yes
Operating temperature range: -30 to +50 °C
Maximum humidity: up to 95% (non-condensing)
Housing color: blue (RAL 5012)
Connection terminals: 6 mm2 / AWG10, screw fastening
Protection rating: IP22
Weight: 0.4 kg
Dimensions (height x width x depth): 100 x 113 x 47 mm