Victron Energy - 12/24V - Cyrix-Li Intelligent Load Relay 12/24V-120A

Victron Cyrix-Li 120A Load Relay: Advanced LiFePO4 Protection

The Victron Cyrix-Li-load 12/24V-120A is an intelligent, heavy-duty relay designed specifically to protect Victron LiFePO4 batteries from damaging deep discharge. While Victron lithium batteries feature integrated cell balancing, a robust second line of defence is essential for long-term battery health. Working seamlessly with the Victron VE.Bus BMS, this load relay automatically disconnects non-smart loads when cell undervoltage is imminent, ensuring your expensive lithium bank remains safe from permanent degradation.

Intelligent Load Management via VE.Bus BMS

In advanced power systems found in caravans, marine vessels, and remote off-grid setups, not all connected loads can be directly controlled by a Battery Management System. The Cyrix-Li-load bridges this critical gap. When the VE.Bus BMS detects an unsafe drop in individual cell voltage, the control input to the Cyrix becomes free-floating. The relay immediately disengages, cutting power to the heavy loads before the battery reaches a critical state.

Once the battery voltage recovers, which typically occurs after the load is removed or a charging cycle begins, the BMS output resets. The Cyrix-Li-load is programmed to wait 30 seconds before re-engaging to prevent rapid, erratic cycling. If it makes three attempts to reconnect without success, it will remain locked open until the battery voltage rises above 13V for 12V systems, or 26V for 24V systems, for at least 30 seconds, confirming that a sustained recharge is actively underway.

Addressing Transient Voltages and System Safety

When disconnecting heavy loads rapidly under fault conditions, significant voltage spikes can occur. This intelligent relay includes advanced internal circuitry to manage these electrical transitions safely. By cleanly severing the connection to demanding appliances, it protects both the lithium battery cells and the sensitive electronics connected to your broader DC distribution network.

Understanding the Cyrix-Li Range

Victron manufactures several versions of the Cyrix-Li relay to perform highly specific tasks within a LiFePO4 ecosystem. While the Cyrix-Li-Charge governs charging sources and the Cyrix-Li-ct handles battery combining, the Cyrix-Li-load is exclusively dedicated to output protection. This strict separation of duties ensures that if an overvoltage event stops your charge cycle, your critical loads can remain powered, and vice versa. Selecting the correct purpose-built relay ensures your VE.Bus BMS functions exactly as intended without compromise.

Key Features

• Automatic Voltage Detection: Smart 12V and 24V auto-ranging capability for simplified system integration.
• High Current Capacity: Rated for up to 120A continuous load handling for demanding equipment.
• Direct VE.Bus BMS Integration: Responds instantly to BMS signals to prevent catastrophic cell undervoltage.
• Anti-Cycling Logic: Built-in 30-second delay and specific voltage thresholds prevent rapid on/off switching.
• Heavy-Duty Terminals: Equipped with robust M8 threaded bolt terminals for highly secure, low-resistance connections.
• Fail-Safe Protection: Disengages immediately if the control input becomes disconnected or free-floating.

Secure Your Power System Today

Ensure the longevity and reliability of your Victron lithium battery bank by integrating the correct protection devices. Upgrade your power management system with the Victron Cyrix-Li Intelligent Load Relay and safeguard your off-grid energy storage.

Specifications