Victron Cyrix-Li-Charge Smart Charging Relay 24/48V-120A

Cyrix-Li-Charge 24/48V-120A Microprocessor Controlled Heavy Duty Relay Automatically Connects batteries in parallel when one of them has reached a predetermined voltage (indicating that the battery is charging) and disconnects when the voltage drops below the floating level (indicating that one or more batteries are discharged). Cyrix battery combiners are an excellent replacement for diode isolators.

The LiFePO4 battery: prevent cell under voltage, over voltage and over temperature
The first line of defense is cell balancing. All Victron LiFePO4 batteries have integrated cell balancing. The second line of defense consists of:

• interrupting the load in the event of an impending live element, and
• shutdown or reduction of charging current in case of impending cell overvoltage, high temperature (>50°C) or low temperature (<0°C).

VE.Bus BMS is the core of the second line of protection. However, not all loads or chargers can be directly controlled by the VE.Bus BMS. Several Cyrix VE.Bus BMS controlled switches are available to disable such loads or chargers.

Cyrix-Li-Charge

The Cyrix-Li-Charge 24/48V-120A will connect a battery charger with a 3 second delay:

• if the VE.Bus BMS charge disconnect output is high and
• if it detects 13,7 V (27,4 V or 54,8 V respectively) or more at the battery charger connection terminal, and
• if it senses 2V or more on its battery terminal (Cyrix will stay on if not connected to battery). The Cyrix-Li-Charge will immediately trip whenever its control input becomes free-floating, signaling cell over voltage or cell over temperature.

Generally, a cell overvoltage alarm will reset shortly after charging is stopped. Cyrix will then reconnect the charger after a 3 second delay. After two attempts to reconnect with a 3 second delay, the delay increases to 10 minutes. Whenever the battery voltage is less than 13,5V (27V or 54V respectively), the Cyrix will disengage with a 1 hour delay.

Note 1: In the case of zero or low discharge current, the Cyrix will not release shortly after the charger is turned off and/or disconnected because the battery voltage will remain higher than 13,5V.
Note 2: If, after the Cyrix is ​​disengaged, the battery charger output immediately rises to 13,7V or more, the Cyrix will reengage, with a 3 second delay.

A built-in transient voltage suppressor will limit the voltage spike that can occur when the Cyrix is ​​suddenly discharged due to cell overvoltage or overtemperature.

Specifications