Victron Cyrix-ct 12/24V 230A Battery Combiner Isolation Relay Battery Protector

Cyrix Battery Combiner

The Cyrix battery combiner is a high-performance, microprocessor-controlled relay that automatically connects batteries in parallel when one of them has reached a predefined voltage (indicating that the battery is being charged) and disconnects the batteries from each other again when the voltage drops below the float voltage (indicating that one or both batteries are being discharged). Cyrix battery combiners are an excellent alternative to diode isolators.
Their main advantage is that there is virtually no voltage loss, so the output voltage of the alternators or battery chargers does not need to be increased.

Product features

• maximum continuous current: 230 A
• permissible starting current (5s): 500 A
• suitable for 12V or 24V systems (automatic detection)
• virtually no voltage loss
• no D+ signal required: The Cyrix battery combiner switches depending on the battery voltage
• Battery temperature protection: In case of high overload, the battery is automatically disconnected

Intelligent battery monitoring to avoid unwanted switching

Some battery combiners (also called voltage-controlled relays or split-charge relays) disconnect a battery when a short but high-amperage load occurs. Sometimes a battery combiner also does not connect a large but discharged battery bank because the DC voltage immediately drops below the disconnection threshold after the batteries have been connected. The software of the Cyrix-ct 12/24 performs more functions than simply connecting and disconnecting based on battery voltage and with a fixed time delay.
The Cyrix-ct 12/24 monitors the general trend (voltage rising or falling) and only reverses a previous action if a trend has reversed over a certain period of time. The time delay depends on the extent to which the voltage deviates from the trend.
 

No voltage loss

Cyrix battery combiners are an excellent alternative to diode isolators.
Their main advantage is that there is virtually no voltage loss, so the output voltage of the alternators or battery chargers does not need to be increased.

Voltage sensing in both directions and power supply from both batteries

The Cyrix measures the voltage of the two connected batteries. It therefore also switches on if, for example, the auxiliary battery is being charged by a battery charger. The Cyrix-ct 12/24 has a dual power supply. It therefore also closes if the voltage of one of the batteries is too low to operate the Cyrix.
To avoid unintended operation during installation or if one of the batteries has been disconnected, the Cyrix-ct 12/24 does not close if the voltage at either battery terminal is below 2 V (12 V battery) or 4 V (24 V battery).

Overheat protection (e.g., due to prolonged overload)

The Cyrix disconnects if the contact temperature is too high and reconnects after the temperature has dropped.

Parallel connection for emergencies (Start Assist)

The Cyrix can also be switched on via a push-button (Cyrix remains active for 30 seconds) or via a switch to manually connect the batteries in parallel. This is particularly useful in an emergency if the starter battery is discharged or damaged.

Documents & Downloads

• Datasheet