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Victron Cyrix-Li-Intelligent Charge Relay 12/24V-120A
Victron Cyrix-Li-Intelligent Charge Relay 12/24V-120A
BMS-Controlled 120A Charge Relay for LiFePO4 - 46x46x80mm IP54
Guaranteed Safe and Secure Checkout
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DESCRIPTION
Victron Cyrix-Li-Charge 12/24V-120A: Intelligent Charge Relay for LiFePO4 Battery Systems
Precision Charge Control for Lithium Battery Protection
The Victron Cyrix-Li-Charge 12/24V-120A is a specialised intelligent charge relay designed to integrate seamlessly with Victron VE.Bus BMS and LiFePO4 lithium batteries. It acts as a critical secondary protection layer, automatically connecting and disconnecting charging sources to prevent cell overvoltage and over temperature conditions. Unlike generic relays, the Cyrix-Li-Charge responds instantly to BMS signals, ensuring your expensive lithium battery bank remains within safe operating limits at all times.
Engineered for 12V and 24V DC systems, this relay handles continuous currents up to 120A, making it suitable for high-power chargers and alternators. Its intelligent logic monitors both the BMS control input and battery voltage, providing automated reconnection only when conditions are safe. This reduces the risk of battery damage from faulty chargers or unexpected voltage spikes, a common issue in mobile and off-grid installations.
How the Cyrix-Li-Charge Protects Your Investment
In a Victron lithium system, the VE.Bus BMS serves as the primary safeguard. However, not all chargers can be directly controlled by the BMS. The Cyrix-Li-Charge bridges this gap by acting as a controllable switch. When the BMS detects an imminent cell overvoltage or high temperature (above 50°C), it sends a signal to the Cyrix, which disengages immediately—cutting off the charging source within milliseconds. This rapid response prevents thermal runaway and extends battery lifespan.
After disconnection, the relay intelligently manages reconnection. It waits for the BMS signal to return high and verifies that the charger output is above 13.7V (12V system) or 27.4V (24V system). A 3-second delay ensures stability before re-engaging. If repeated faults occur, the delay extends to 10 minutes, preventing rapid cycling that could stress system components. Additionally, if battery voltage drops below 13.5V (27V for 24V) for an hour, the relay disengages to avoid unnecessary drain.
Key Features at a Glance
- Instant BMS-driven disconnection for overvoltage and over temperature protection
- 120A continuous rating at 12V/24V, with 40A breaking capacity at 48V
- Automatic reconnection logic with progressive delays to prevent cycling
- Low power consumption (<4mA when open) ideal for energy-conscious systems
- Compact, robust design (46x46x80mm, 0.11kg) with IP54 protection
- Built-in transient voltage suppression to protect against inductive spikes
- Clear status LED for quick operational diagnostics
Seamless Integration with Victron Energy Systems
The Cyrix-Li-Charge is purpose-built for Victron's ecosystem, connecting directly to the VE.Bus BMS control output. It requires a minimum of 2V on its battery terminal to operate, ensuring it remains open if accidentally disconnected from the battery—a safety feature that prevents uncontrolled charging. The relay's 3/8"-16 (Approx. M10) stud terminals accommodate heavy-duty lugs up to 4/0 AWG (approx. 95mm²), ensuring secure, low-resistance connections for high-current applications.
For installers, the integrated mounting tabs and pre-drilled holes simplify fixed installations in battery compartments, engine bays, or electrical cabinets. The IP54 rating provides protection against dust and water splashes, making it reliable in marine, RV, and off-grid environments where conditions can be harsh.
Applications: Where Precision Charging Matters
This relay is essential for any Victron lithium setup where charging sources cannot be directly managed by the BMS. Typical use cases include:
- Marine and RV electrical systems with high-output alternators or shore power chargers
- Off-grid solar installations using MPPT controllers that lack BMS communication
- Backup power systems where generator or grid chargers need automated disconnect
- Industrial battery banks requiring fail-safe charge termination
By isolating the charger during fault conditions, the Cyrix-Li-Charge prevents overcharging that could lead to cell degradation or safety hazards. It also eliminates the need for manual intervention, allowing unattended systems to operate safely.
Why Choose the Cyrix-Li-Charge Over Generic Relays?
Standard automotive relays lack the intelligence to interpret BMS signals or monitor voltage thresholds. They simply switch on or off, offering no protection against overvoltage or temperature extremes. The Cyrix-Li-Charge, in contrast, actively communicates with the BMS and applies conditional logic to ensure charging only occurs when safe. This reduces the risk of battery failure, which can be costly and dangerous in lithium systems.
Additionally, the built-in transient voltage suppressor protects against voltage spikes that occur when the relay disconnects under load—a common cause of contact welding in inferior relays. This extends the relay's operational life and maintains system integrity.
Installation and Compatibility Notes
The Cyrix-Li-Charge is designed for use with Victron LiFePO4 batteries and the VE.Bus BMS. It is not a standalone battery protect device; for load disconnection, consider the Victron BatteryProtect. Always ensure proper fusing and cable sizing according to system current. The relay's control input engages when high (approx. battery voltage) and disengages when free-floating or pulled low, making it compatible with standard BMS outputs.
For systems requiring combined charging and load control, the Cyrix-Li-ct (battery combiner) or Cyrix-Li-load (load disconnect) variants may be more appropriate. Contact our team for assistance with system design if you're unsure which model suits your application.
Secure Your Lithium Battery System Today
Protect your investment with the Victron Cyrix-Li-Charge 12/24V-120A. Whether you're upgrading an existing installation or building a new off-grid power system, this intelligent relay provides the precision control needed for safe, reliable lithium charging. Order now to ensure your battery bank operates within safe limits, every cycle.
SKU: Vic-CYR010120430
SPECIFICATIONS
Specifications
| Model | Cyrix-Li-Charge 12/24-120 |
|---|---|
| System Voltage | 12/24 V |
| Continuous Current And Breaking Capacity At 12 V Or 24 V | 120 A |
| Breaking Capacity At 48 V | 40 A |
| Connect Delay | 3 s |
| Connect Voltage | 13.0 V (12 V), 26.0 V (24 V) |
| Minimum Battery Terminal Voltage | 2 V |
| Control Input | Engages when the control input is high (appr. battery voltage); disengages when the control input is left free floating or pulled low. |
| Charger Check Interval When Engaged | 1 hour |
| Current Consumption When Open | <4 mA |
| 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) |
| SKU: | Vic-CYR010120430 |
| Barcode: | 8719076022183 |
| Model #: | CYR010120430 |
| MPN: | CYR010120430 |
WARRANTY
Victron Energy Limited Warranty Policy
Direct Customers
Victron Energy provides the following warranty to any direct customer (OEM, distributor or dealer) in relation to any products that Victron Energy has directly sold to the direct customer. This warranty is not an end-user warranty between Victron Energy and an end-user, and end-users shall not have any rights or remedies under this limited warranty towards Victron Energy directly. The direct customer shall, in turn, ensure that the end-user is provided with a warranty identical to this warranty, subject to applicable local mandatory law.
End-Users
Victron Energy may also provide a warranty directly to end-users, in which case the below warranty conditions equally apply to such warranty. In that case, end-users shall claim their warranty at their place of purchase or through the original direct customer of Victron, which can be found through the support section on Victron’s website https://www.victronenergy.com/support. Hence, the direct customer shall on behalf of Victron Energy deal with any warranty claims made under any warranty that Victron Energy may provide directly to end-users. This support section on Victron’s website https://www.victronenergy.com/support will provide further guidance on the procedure for end-users to make a claim under this limited warranty.
If the end-user is a consumer – a natural person who is acting for purposes which are outside that person's trade, business, craft or profession – the following applies. The rights and remedies granted to the consumer under this limited warranty are without prejudice to the consumer’s statutory rights. Furthermore, the consumer is entitled by law to remedies from the seller free of charge in the event of a lack of conformity of the goods (such as repair, replacement, price reduction or rescission), which remedies are not affected by this limited warranty.
Warranty
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 original 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 original end-user, with a maximum of 30 months from the Victron Energy invoice date, Lithium batteries: 3 years from date of purchase by the original end-user, with a maximum of 42 months from the Victron Energy invoice date. In addition to this, proof of correct battery usage is required when making a battery warranty claim.
For a 10% surcharge on the current net price for products that came with a 5-year warranty, an additional 5 years of warranty can be purchased by Victron’s direct customers, bringing the total warranty to 10 years. Warranty extensions need to be applied for ultimately one year before the expiration of the original term. Victron may ask proof that the product was still functional at the time of purchase of the extended warranty.
During the warranty period, Victron Energy will, at its discretion, repair, replace or (partly) credit 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:
- Reversed battery polarity.
- Inadequate connection.
- Mechanical shock or deformation.
- Contact with liquid or oxidation by condensation.
- Use in an inappropriate environment (dust, corrosive vapour, humidity, high temperature, biological infestation, etc.).
- Breakage or damage due to lightning.
- Connection terminals and screws destroyed or other damages, like overheating, due to insufficient tightening.
- For any electronic breakage except due to lightning (reverse polarity, over‐voltage due to external cause), the state of the internal control diode and/or the input/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 other than Victron Energy or one of its authorized Repair Centres. In order to qualify for the warranty, the product must not be disassembled or modified.
This warranty and our warranty obligations thereunder (repair, replacement or credit) are the direct customer’s and, if applicable, the end-user’s sole rights and remedies and our sole obligations with respect to any defective and/or non-conforming product or breach of warranty and is subject to and without prejudice to the limitations of liability in this warranty.
Victron Energy shall not be liable for damages, whether direct, incidental, special, or consequential, even caused by negligence or fault.
As a product requires service, it must be brought back to the place of purchase. In case no contact can be made with the merchant, or if he is either unable or not allowed to provide service, direct contact should be made with Victron Energy through the support section on Victron’s website.
In case Victron Energy replaces a product, it will own the replaced product. Victron Energy owns all parts removed from repaired products. Victron Energy uses new or reconditioned parts made by various manufacturers when performing warranty repairs or building replacement products.
If Victron Energy repairs or replaces a part of a product, its warranty term is not extended: the warranty will apply for the remaining term of the original warranty term. For example, if Victron Energy replaces a product with a 5-year warranty after 3 years, the warranty of this product will apply for another 2 years, with a minimum of 6 months.
All remedies and the measure for damages are limited to the above. Victron Energy shall in no event be liable for consequential, incidental, contingent or special damages, even if having been advised of the probability of such damages.
The foregoing limited warranty provided by Victron Energy is in lieu of any other warranties, express or implied arising by law, course of dealing, course of performance, usage of trade or otherwise, of any kind whatsoever including, without limitation, warranties of merchantability or fitness for a particular purpose, with respect to any product. The above is without prejudice to the arrangement for consumers detailed above.
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 Victron Energy's product can be reasonably expected to cause the 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.
Warranty on repairs for products outside their warranty period
The warranty period on products that are outside their warranty period and have been repaired by Victron Energy or one of the Victron Energy Repair centres is six (6) months from delivery. The same applies to spare parts and circuit boards that have been supplied or repaired 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 of this warranty 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 of this warranty.
Applicable law
This warranty is exclusively governed by the laws of the Netherlands, to the exclusion of the UN Convention on Contracts for the International Sale of Goods.
Contact details
Victron Energy B.V. | De Paal 35, 1351 JG Almere, The Netherlands | https://www.victronenergy.com/support
