Victron Energy Battery Balancer

Product detailed description

Victron Energy Battery Balancer
The life of a battery bank can be significantly shortened by charging imbalances of individual batteries. This is a situation where you have series or series-parallel 12 V batteries (not just in parallel!). In such a system, a single 12 V battery with a slightly higher internal resistance can cause undercharging to full state for series-parallel batteries and overcharging for series-parallel batteries. New battery cells or whole batteries in series have almost identical initial characteristics. Their minor differences are aligned during the absorption or equalization phase of charging. However, large differences can lead to excessive gassing caused by overcharging in more highly charged batteries and undesirable sulphation in less highly charged batteries caused by undercharging to full state.

The solution is balanced charging using a battery balancer. This balances the state of charge of two series-connected 12 V batteries or several parallel rows of series-connected batteries. As soon as the charging voltage rises to more than 27.3 V in a 24 V system, the battery balancer is activated and compares the voltage of the two batteries in series. The balancer can redirect a current of up to 0.7 A from one battery (or batteries connected in parallel) of a higher voltage to the other battery. The different charging current results in a mutually identical final state of charge for all batteries.

Battery balancers can also be sorted in parallel for a more complex system. For a 48 V system, a total of three balancers are thus used (see diagrams).

Explanation of LED indicators:
Green LED: the device is active and the measured voltage is higher than 27.3 V
Top orange LED: voltage deviation is greater than 0.1 V
Lower orange LED: voltage deviation is greater than 0.1 V
Red LED: triggering an alarm if the difference between the monitored batteries is greater than 0.2 V. The alarm persists until the difference is less than 0.14 V or the system voltage drops to less than 26.6 V

The importance of the alarm relay
In the default state it is open (inactive). It is closed (activated) when the red LED lights up, i.e. when the voltage difference between the batteries is higher than 0.2 V. As soon as the red LED goes out, the relay is opened (deactivated) again (the voltage difference between the batteries is less than 0.14 V).

Alarm reset
Turning off the alarm is achieved by interconnecting the outputs marked as RESET. This can be done by means of a switch.

installation
1) The battery balancer(s) must be installed on a well-ventilated vertical surface close to 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 reset wiring.
3) Use at least 0.75 mm2 size cable to connect the negative, positive and middle pole (in that 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 will illuminate, indicating that the balancer is activated. If in this situation the deviation of the batteries (strings) is greater than 50 mV, active balancing, i.e. compensation of the difference of the batteries (strings), starts .If the deviation reaches 100 mV, one of the orange LEDs is activated. A deviation greater than 200 mV triggers an alarm relay.
For series-parallel battery arrangements, the intermediate interconnecting wiring between the parallel rows must be sized to handle the appropriate 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 deactivating the balancer: 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 100 mV deviation and above
Voltage deviation for alarm triggering: 200 mV
Voltage deviation for alarm tripping: 140 mV
Alarm relay: 60V / 1 A, standard open
Alarm relay tripping method: connecting two outputs marked as RESET
Overheating protection: yes
Operating temperature range: -30 to +50°C
Maximum humidity: up to 95% (non-condensing)
Cover colour: blue (RAL 5012)
Connection contacts: 6 mm2 / AWG10, screw attachment
Degree of protection: IP22
Weight: 0,4 kg
Dimensions (height x width x depth): 100 x 113 x 47 mm