Victron Cyrix-i 12/24V 400 A battery coupler isolating relay battery protection

Cyrix-i intelligent battery coupler

The cyrix battery coupler is a high performance microprocessor controlled relay that automatically connects batteries in parallel when one of them has reached a predetermined voltage value (thereby indicating that the battery is charging) and that separates the batteries again when the voltage drops below the float voltage value (thereby indicating that one or both batteries are being discharged).
cyrix battery couplers are ideal for replacing isolating diodes. Their main feature is that there is practically no voltage loss, so the output voltage of the alternators or battery chargers does not need to be increased.

Product features

• Maximum continuous current: 400 A
• permissible starting current (1s): 2000 A
• suitable for 12V or 24 V systems (automatic detection)
• practically no voltage loss

New: pioneering battery monitoring prevents unwanted switching operations

Some battery control relays trigger disconnections when high currents are applied for a short time. It can also happen that a large but empty battery group cannot be connected because the voltage drop when connecting causes the threshold for disconnection to be undercut.
The software stored in the Cyrix-i does not only refer to voltage values ​​and fixed time intervals. Rather, Cyrix-i takes the trend (voltage/time curves) into account and only intervenes if the trend changes over a certain time interval. The time delay is proportional to the voltage deviation from the trend curve. In addition, four different switching/time curves can be set

Automatic range selection at 12/24V

Cyrix-i automatically detects the applied system voltage.

No voltage loss

The Cyrix-i battery controller is the alternative to isolating diodes. Since there is practically no voltage loss, there is no need to increase the charging voltage on the alternator or charger, which is otherwise necessary to compensate for the loss.

Priority circuit for the starter battery

Typically, the alternator is connected directly to the starter battery. The on-board battery, possibly the bow thruster battery and others are connected via Cyrix-i devices. Only when the starter battery has reached the appropriate voltage does Cyrix-i switch on the other batteries for parallel charging.

Bidirectional voltage measurement and power supply

Cyrix-i measures the voltage values ​​of the connected battery groups. It therefore typically reacts even when the on-board battery is being charged by a charger. The Cyrix-i has a dual power supply. It therefore works even if one of the connected batteries has too little voltage for Cyrix-i operation.
To avoid unwanted switching during installation or after disconnecting the battery connection, Cyrix-I will not switch if the voltage value of one of the two battery connections falls below 2V (12V battery), 4V (24V battery) or 8V (48V battery).

Parallel connection in case of emergency

The Cyrix-i can also be switched on using a push button (Cyrix-i then remains switched on for 30 seconds). There is also a switch for manually connecting the batteries in parallel. This is particularly useful if the starter battery is empty or damaged in an emergency.