Victron Energy Cyrix-ct 12/24-Volt 120 Amp Battery Combiner Kit User Manual

1. Introduction and Overview

The Victron Energy Cyrix-ct 12/24-Volt 120 Amp Battery Combiner Kit is designed to manage multiple battery systems in vehicles such as cars, boats, and RVs. It ensures all batteries are charged efficiently by the engine's electrical system while isolating the starting battery when charging ceases, preventing discharge. This intelligent, bidirectional voltage-sensitive relay automatically connects and disconnects batteries based on voltage levels, optimizing charging and preventing cycling.

Figure 1: Victron Energy Cyrix-ct Battery Combiner Kit packaging, showing the combiner unit, cables, and accessories.

Figure 2: Diagram illustrating key features of the Victron Energy Cyrix-ct: microprocessor controlled, 100A max charge current, 2 battery support, easy installation.

2. What's in the Box

The Victron Energy Cyrix-ct Battery Combiner Kit includes the following components:

• Cyrix-ct Intelligent Battery Combiner
• 6m RED 10mm² cable
• 0.5m BLACK 10mm² cable
• 0.2m BLACK 1.5mm² cable assembly with M8 lug and 6.3mm fast on terminal
• 2pcs M8 cable lug with insulation sleeve
• 4pcs M6 cable lug with insulation sleeve
• 4pcs cable tie 150mm

Figure 3: Contents of the Victron Energy Cyrix-ct Battery Combiner Kit, including the Cyrix-ct unit, red and black cables, cable lugs, and cable ties.

3. Specifications

Figure 4: Dimensions of the Victron Energy Cyrix-ct 12/24V-120A Intelligent Battery Combiner, showing measurements of 80mm (3.2 inches) height and 46mm (1.8 inches) width.

4. Setup and Installation

The Cyrix-ct is designed for easy installation, requiring no cutting into factory wiring. It is suitable for adding a second or third battery system in various vehicles.

Installation Steps:

1. The Cyrix can only be used in 12V, 24V or 48V installations with a negative common.
2. Disconnect the negative terminals of both batteries.
3. Place the Cyrix closest to the smallest battery (generally the starter battery).
4. Connect the positive terminals of the batteries to the brass bolts of the Cyrix, marked with no 30 and 87 respectively. Install a fuse in series. The fuse should be sized in accordance with the wire cross-section used, but not exceed 120A.
5. Connect the negative terminal of the Cyrix "battery -" (86) and reconnect the negative terminals of both batteries.
6. An emergency start push button can be wired to the "start assist" connection (85) if required. The relay will engage during 30 seconds after "start assist" has been momentarily connected to the battery plus. Alternatively, a parallel connect switch can be used to engage the relay as long as the switch remains closed.

Figure 5: Quick guide installation diagram for the Victron Energy Cyrix-ct, showing connections between alternator, starter motor, starter battery, domestic battery, and the Cyrix-ct unit with fuses.

Installation Demonstration Video:

5. Operating Principles

The Cyrix-ct operates as an intelligent battery combiner, ensuring optimal charging for all connected batteries. It functions as a bidirectional voltage-sensitive relay.

Intelligent Battery Monitoring:

The software within the Cyrix-ct does more than simply connect and disconnect based on battery voltage and a fixed time delay. It monitors the general trend of voltage (increasing or decreasing) and reverses a previous action only if the trend has reversed over a certain period. The time delay is adaptive, depending on the voltage deviation from the trend.

When the Cyrix senses that the starter battery has reached the connect voltage, it will engage to allow for parallel charging of the other batteries. This prioritizes the starter battery while ensuring auxiliary batteries also receive a charge.

Figure 6: Diagram showing the Cyrix-ct prioritizing the starter battery for charging, then allowing parallel charging of other batteries once the starter battery reaches a set voltage.

Battery Monitoring with BMV-712 Smart:

Accurate battery information for both service and starter batteries can be displayed on a Bluetooth-enabled BMV-712 Smart Battery Monitor (sold separately). This allows users to monitor battery status, voltage, and current in real-time.

6. Maintenance

The Victron Energy Cyrix-ct is designed for reliable, long-term operation with minimal maintenance. Regularly inspect all cable connections for tightness and corrosion. Ensure the unit is free from dirt, dust, and moisture. No user-serviceable parts are inside the Cyrix-ct unit. For any issues, refer to the troubleshooting section or contact customer support.

7. Troubleshooting

If you encounter issues with your Cyrix-ct Battery Combiner Kit, consider the following general troubleshooting steps:

• No Connection/Charging: Verify all cable connections are secure and free from corrosion. Check fuses in the system. Ensure battery voltages are within the operating range for the Cyrix-ct to engage.
• Incorrect Voltage Readings: If using an external battery monitor, ensure it is correctly calibrated and connected.
• Over-current/Over-temperature Protection: The Cyrix-ct includes built-in protection. If it disengages unexpectedly, check for excessive current draw or overheating. Allow the unit to cool down if necessary.

For persistent issues, consult the detailed manual available on the Victron Energy website or contact Victron Energy customer support.

8. Warranty and Support

Victron Energy products are manufactured to high standards and come with a manufacturer's warranty. For specific warranty details, including coverage period and terms, please refer to the documentation included with your product or visit the official Victron Energy website. Technical support and additional resources can also be found on the Victron Energy website.

Protection plans may be available for extended coverage. Please check with your retailer or Amazon for details on available protection plans.