The Victron Cyrix-CT 12/24V-230A Battery Combiner – CYR010230010 is a microprocessor controlled heavy-duty relay that automatically connects batteries in parallel when one battery has reached a preset voltage (indicating that the battery is charging), and disconnects when the voltage drops below the float level (indicating that one or more batteries are discharging). Cyrix battery combiners are an excellent substitute for diode isolators. The main feature is that there is virtually no voltage loss, so there is no need to increase the output voltage of alternators or battery chargers.

Victron Cyrix-CT 12/24V-230A Battery Combiner – CYR010230010: Intelligent battery control to avoid unwanted switching

Some battery combiners (also called voltage-controlled relays or split-load relays) disconnect a battery in the event of a short but high amperage load. A battery combiner can also fail when connecting a large but discharged battery bank because the DC voltage drops immediately below the disconnect value once the batteries are connected. The software of the Cyrix-ct 12/24 does more than simply switch on and off depending on the battery voltage and with a fixed time delay. The Cyrix-ct 12/24 observes the general trend (voltage increase or decrease) and reverses a previous action only if the trend has been reversed for a certain period of time. The time delay depends on the voltage deviation from the trend.

Protection against overheating (e.g. by long-term overloading)

The Cyrix switches off in case of excessive contact temperature and switches on again when it has cooled down.

LED status indicator

LED on: activated
10 s LED flashing: off
LED flashing for 2 s: switching on
LED flashing for 2 s: switching off
0.25 s LED flashing: alarm (overtemperature; voltage > 16 V; both batteries < 10 V; one battery < 2 V) (multiply by two for 24 V)

12/24V self-regulating

The Cyrix-ct 12/24 automatically detects the system voltage.

Victron Cyrix-CT 12/24V-230A Battery Combiner – CYR010230010: No voltage loss

Cyrix battery combiners are an excellent substitute for diode isolators. The main feature is that there is virtually no voltage loss, so there is no need to increase the output voltage of alternators or battery chargers.

Starter battery priority

In a typical configuration, the alternator is connected directly to the starter battery. The accessory battery, and possibly also a bow thruster and other batteries, are connected to the starter battery with Cyrix battery combiners. When a Cyrix detects that the starter battery has reached the connection voltage, it connects to allow parallel charging of the other batteries.

Bi-directional voltage sensing and power supply of both batteries

The Victron Cyrix-CT 12/24V-230A – CYR010230010 battery combiner detects the voltage of the two connected batteries. It will therefore also switch on if, for example, the accessory battery is being charged by a battery charger.

The Cyrix-ct 12/24 has a dual power supply. Therefore, it will also shut down if the voltage of one of the batteries is too low to operate the Cyrix.

To avoid unexpected operation during installation or when one of the batteries has been disconnected, the Cyrix-ct 12/24 will not shut down if the voltage on one of the two battery connections is less than 2 V (12 V battery) or 4 V (24 V battery).

Parallel connection in case of emergency (StartAssist)

The Cyrix can also be connected with a button (the Cyrix remains connected for 30 seconds) or a switch to connect the batteries in parallel manually.

This is especially useful in an emergency when the starter battery is discharged or damaged.

Datasheet Victron Cyrix-CT 12/24V-230A Battery Combiner – CYR010230010

View Victron Cyrix-CT 12/24V-230A Battery Combiner – CYR010230010 datasheet