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Victron Cyrix-ct Intelligent Battery Combiner 12/24V-120A VSR
120A Continuous, Trend Detection, Bidirectional, Start Assist, IP54
Victron Cyrix-ct Intelligent Battery Combiner K...DESCRIPTION
Victron Cyrix-ct 120A Intelligent Battery Combiner for Dual Battery Systems
Advanced Voltage Sensing Relay with Trend Detection for Reliable Parallel Charging
The Victron Cyrix-ct 12/24V-120A is a microprocessor-controlled intelligent battery combiner that functions as a bidirectional voltage sensitive relay (VSR). Unlike conventional split charge relays that rely on simple voltage thresholds and fixed time delays, the Cyrix-ct analyses the overall voltage trend to prevent nuisance switching. This ensures your auxiliary battery bank charges reliably from the alternator or mains charger without premature disconnection under heavy loads or reconnection when surface charge dissipates.
Engineered for 12V and 24V automotive and marine electrical systems, the Cyrix-ct auto-detects system voltage and provides a continuous current rating of 120 A, making it suitable for charging large domestic battery banks, bow thruster batteries, and other onboard equipment. Its bidirectional sensing allows the combiner to engage when either battery reaches the connect voltage, so charging sources on either side can parallel the banks automatically.
Intelligent Trend Detection Eliminates Unwanted Cycling
Standard voltage-controlled relays often disconnect a battery when a short, high-current load causes a momentary voltage dip, or fail to connect a deeply discharged bank because the voltage collapses below the disconnect threshold immediately after engagement. The Cyrix-ct’s software monitors the rate and direction of voltage change over time, reversing a previous action only if the trend has genuinely reversed. The time delay adapts based on the deviation from the trend, providing stable operation in demanding conditions.
Key Features
- 120 A continuous current rating with 180 A cranking assist for emergency parallel starts
- 12/24 V auto-ranging detects system voltage automatically, no manual configuration needed
- Bidirectional voltage sensing and dual power supply allows engagement from either battery, even if one is deeply discharged
- Start Assist function via push button or switch provides 30-second emergency parallel connection
- Over-temperature protection disengages the relay if contact temperature becomes excessive, re-engaging after cooling
- Virtually zero voltage drop across the contacts, eliminating the need to increase alternator or charger output voltage
- Prioritises starter battery by connecting auxiliary banks only after the starter reaches the connect voltage
- Compact IP54-rated housing (46 x 46 x 80 mm) withstands dust and water spray in engine bays and marine compartments
- Low power consumption: less than 4 mA when open, 220 mA (12 V) or 120 mA (24 V) when closed
- 13 mm (M6) long stud terminals allow secure connection of multiple heavy-duty cable lugs
Reliable Parallel Charging Without Voltage Loss
Diode-based battery isolators introduce a voltage drop of 0.6–0.7 V, which can prevent full charging unless the alternator or charger is voltage-boosted. The Cyrix-ct uses a high-current relay with negligible contact resistance, so your batteries receive the full charging voltage. This makes it a direct, efficient replacement for diode isolators in 12V dual battery systems and 24V marine setups.
Emergency Start Assist for Peace of Mind
If your starter battery becomes discharged or damaged, the Cyrix-ct can be manually engaged using a momentary push button or switch connected to the Start Assist terminal. The relay remains closed for 30 seconds, allowing you to draw power from the auxiliary bank to crank the engine. This feature is invaluable for remote travel, off-grid work sites, and marine applications where a flat starter battery could leave you stranded.
Designed for Harsh Environments
With an operating temperature range of -40 to +60 °C and an IP54 protection rating, the Cyrix-ct is built to perform in engine compartments, bilges, and exposed vehicle installations. The fully sealed housing resists dust ingress and water spray, while the robust M6 stud terminals accept heavy-gauge cable lugs for secure, low-resistance connections.
Typical Applications
- Charging a second battery in 4WD, caravan, and camper trailer dual battery systems
- Marine installations with separate start and house battery banks
- Bow thruster and windlass battery charging
- Commercial vehicles and agricultural machinery with auxiliary power requirements
- Off-grid solar systems where multiple battery banks need to be combined during charging
Installation and Wiring
The Cyrix-ct features clearly labelled M6 stud terminals for Battery 1 (Terminal 87) and Battery 2 (Terminal 30), plus spade terminals for the negative sensing wire (Terminal 86) and optional Start Assist switch (Terminal 85). A wiring diagram is included in the product images to guide installation. For systems requiring multiple engage/disengage profiles, consider the Victron Cyrix-i 400.
Upgrade Your Dual Battery System with Intelligent Control
Replace unreliable diode isolators and basic voltage-sensing relays with the Victron Cyrix-ct 120A Intelligent Battery Combiner. Its trend-detection logic, bidirectional sensing, and emergency start assist provide dependable parallel charging for your auxiliary batteries. Order today to ensure your onboard power system operates efficiently and reliably, wherever your journey takes you.
SKU: Vic-CYR010120011
SPECIFICATIONS
Specifications
| Victron Part Number | CYR010120011 |
|---|---|
| Model | Cyrix-ct 12/24-120 |
| Product Type | Intelligent Battery Combiner |
| System Voltage | 12/24 V Auto Ranging |
| LED Status Indication | No |
| Continuous Current | 120 A |
| Cranking Rating (5 s) | 180 A |
| Connect Voltage | From 13 V to 13.8 V and 26 to 27.6 V, with intelligent trend detection |
| Disconnect Voltage | From 11 V to 12.8 V and 22 to 25.7 V, with intelligent trend detection |
| Current Consumption When Open | <4 mA |
| Current Consumption When Closed | 12 V: 220 mA; 24 V: 120 mA |
| Operating Temperature Range | -40 to +60 °C |
| Start Assist | Yes (Cyrix remains engaged during 30 s) |
| Control Cable Included (Length 1 m) | No |
| Protection Category | IP54 |
| Weight | 0.11 kg (0.24 lbs) |
| Dimensions (H x W x D) | 46 x 46 x 80 mm (1.8 x 1.8 x 3.2 in) |
| Long Bolts | 13 mm (M6) |
| SKU: | Vic-CYR010120011 |
| Barcode: | 8719076022138 |
| Model #: | CYR010120011 |
| MPN: | CYR010120011 |
WARRANTY
Victron Energy Limited Warranty Policy
Victron Energy warrants its products to be free from defects in workmanship and materials for a period of 5 years from the date of purchase by the end user, with a maximum of 66 months from the Victron Energy invoice date. Exceptions on this are: lead acid batteries; 2 years from date of purchase by the end user, with a maximum of 30 months from the Victron Energy invoice date, Lithium-ion batteries; 3 years from date of purchase by the end user. In addition to this proof of correct battery usage is required when making a battery warranty claim.
During this period, Victron Energy will, at its option, repair or replace the defective product free of charge. The warranty does not include performing or reimbursing de‐installation, transportation and re‐installation. This warranty will be considered void if the unit has suffered any physical damage or alteration, either internally or externally, and does not cover damages arising from improper use like: • Reverse of battery polarity. • Inadequate connection. • Mechanical shock or deformation. • Contact with liquid or oxidation by condensation. • Use in inappropriate environment (dust, corrosive vapor, humidity, high temperature, biological infestation...). • Breakage or damage due to lightning. • Connection terminals and screws destroyed or other damages, like overheat, due to insufficient tightening. • For any electronical breakage except due to lightning (reverse polarity, over‐voltage due to external cause), the state ofthe internal control diode and of the inputs/output X and Y capacitors determine the warranty.
This warranty will not apply where the product has been misused, neglected, improperly installed, or repaired by anyone else than Victron Energy or one of its authorized Qualified Service Partners. In order to qualify for the warranty, the product must not be disassembled or modified.
Repair or replacement are our sole remedies and Victron Energy shall not be liable for damages, whether direct, incidental,special, or consequential, even caused by negligence or fault.
Victron Energy owns all parts removed from repaired products. Victron Energy uses new or reconditioned parts made by various manufacturers in performing warranty repairs and building replacement products. If Victron Energy repairs or replaces a part of a product, its warranty term is not extended. In case of replacement the new component has a warranty of 6 months, without effect on the initial warranty period. All remedies and the measure for damages are limited to the above. Victron Energy shall in no event be liable for consequential, incidental, contingent orspecial damages, even if having been advised of the probability of such damages. Any and all other warranties expressed or implied arising by law, course of dealing, course of performance, usage of trade or otherwise, including but not limited to implied warranties of merchantability and fitness for a particular purpose, are limited in duration to a period of two (2) years from the date of purchase.
Life Support Policy As a general policy, Victron Energy, does not recommend the use of any of its products in life support applications where failure or malfunction of the Victron Energy's product can be reasonably expected to cause failure of the life support device or to significantly affect its safety or effectiveness. Victron Energy does not recommend the use of any of its products in direct patient care. Victron Energy will not knowingly sell its products for use in such applications unless it receives in writing assurances satisfactory to Victron Energy that the risks of injury or damage have been minimized, the customer assumes all such risks, and the Liability of Victron Energy is adequately protected under the circumstances.
As a product requires service, it must be brought back to the place of purchase. In case no contact can be taken with the merchant, or if he is either unable or not allowed to provide service, direct contact should be taken with Victron Energy.
Warranty on Repairs The warranty period on products or on printed circuits boards repaired by Victron Energy as well as on printed circuit boards for replacement is 6 months from delivery by Victron Energy.
Transport It is the responsibility of the sender to sufficiently package these products. The transport must be organized in a way to avoid any damage, especially when a single unit or heavy unit is sent.
Severability If a part of the terms and conditions set out above is held invalid, void or unenforceable due to any particular national or international legislation, it shall not affect other parts of the terms and conditions remaining.
For Australia only Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.
Exotronic provides high-quality products and solutions tailored for B2B and commercial customers, including commercial businesses, caravan manufacturers, marine electricians, OEMs, as well as emergency services, and more.
