12V/24V 50A Buck-Boost DC/DC Converter

⚡ VICTRON 12V/24V 50A BUCK-BOOST DC/DC CONVERTER

Programmable 50A DC-DC Service Battery Charger – 12V & 24V Systems, Smart Alternator Compatible, Engine-Running Detection & Input Current Limiting

⚡ The Victron 12V/24V 50A Buck-Boost DC/DC Converter is designed for charging compatible 12V or 24V service batteries from vehicle electrical systems equipped with modern intelligent or smart alternators.

Smart alternators used in many Euro 5, Euro 6 and regenerative-braking vehicles do not necessarily maintain a traditional fixed charging voltage while the engine is running. Depending on vehicle operating conditions, alternator output can rise or fall significantly, making reliable auxiliary-battery charging difficult without appropriate DC-DC control.

The Victron Buck-Boost solves this by providing a controlled charging supply to the auxiliary battery rather than simply passing the vehicle's fluctuating voltage directly through to the service-battery system.

This highly flexible converter can be programmed for compatible 12V or 24V auxiliary batteries supplied from either a 12V or 24V alternator and starter-battery system.

Built-in engine-running detection helps prevent unnecessary discharge of the vehicle's starting battery, while programmable activation, PC configuration, charge-current control and input-current limiting allow the system to be tailored to the vehicle and auxiliary-battery installation.

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⚡ KEY FEATURES

🔋 50A Buck-Boost DC-DC Converter
The product designation identifies this as the 50A version of Victron's programmable Buck-Boost converter range.

🚗 Smart Alternator Compatible
Designed for compatible vehicles using intelligent or smart alternators, including applications associated with regenerative braking and Euro 5 and Euro 6 engines.

🔋 12V or 24V Service Battery Charging
Can be programmed for compatible 12V or 24V auxiliary-battery systems.

⚡ 12V or 24V Vehicle Supply
Can operate in compatible installations using either a 12V or 24V alternator and starter-battery system.

⬆️⬇️ Buck-Boost Voltage Control
Designed to provide controlled charging when the vehicle supply voltage can move above or below the voltage required by the service battery.

🚦 Built-In Engine-Running Detection
Helps prevent deep discharge of the vehicle's starter battery by controlling converter activation according to engine-running conditions.

🎛️ Programmable Activation Input
Can alternatively be activated using a programmable D+, CAN bus* or (+)15 input according to the supplied information.

💻 Fully PC Programmable
Configuration can be adjusted using a dedicated PC application.

🔌 USB Programming Connection
A USB Type-A male to USB Type-B male cable is required for programming according to the supplied information.

⚡ Maximum Charge-Current Setting
The converter's available output is influenced by the programmed maximum charge-current setting.

🔌 Maximum Input-Current Limiting
Input current can also be limited to suit the source electrical system.

🌡️ Temperature-Based Current Limiting
Available output current can also be reduced according to the converter's maximum operating-temperature limit.

💡 Input Status LED
Colour-coded indication provides information about converter operation, low input voltage, engine-running detection and over-temperature conditions.

💡 Output Status LED
Provides clear indication of converter operation and service-battery voltage condition.

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🚗 BUILT FOR MODERN SMART-ALTERNATOR VEHICLES

Traditional alternators generally maintain a relatively consistent charging voltage while the engine is operating.

Modern intelligent alternators can behave very differently. Their output may be actively controlled by the vehicle electronics and can rise or fall significantly according to operating conditions.

The supplied product information specifically identifies compatibility with applications involving:

• 🚙 Smart or intelligent alternators
• ♻️ Regenerative-braking systems
• ⚙️ Euro 5 engine applications
• ⚙️ Euro 6 engine applications

The Buck-Boost converter is designed to provide the auxiliary battery with a controlled charging supply despite these changing vehicle-system conditions.

⚠️ IMPORTANT: Euro 5 or Euro 6 classification alone does not determine the exact alternator strategy used in a particular vehicle. Confirm the actual vehicle charging system before installation.

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⬆️⬇️ BUCK-BOOST CHARGING TECHNOLOGY

The Buck-Boost design allows the converter to manage vehicle-system voltage that may be either too high or too low for reliable auxiliary-battery charging.

The converter charges the service battery using a pre-set charging voltage instead of simply allowing the alternator voltage to determine the charging conditions.

The supplied information gives approximately 15.4V on some Mercedes applications as an example of a higher vehicle-system voltage that the converter can regulate for the auxiliary-battery system.

This also helps maintain charging when the smart alternator reduces its output voltage during other driving conditions.

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🔋 FLEXIBLE 12V & 24V SYSTEM CONFIGURATION

The supplied product information states that the converter can be programmed to charge either a 12V or 24V auxiliary battery from either a 12V or 24V alternator and starter-battery system.

Compatible system arrangements can therefore include:

• 12V source → 12V service battery
• 12V source → 24V service battery
• 24V source → 12V service battery
• 24V source → 24V service battery

This gives the Buck-Boost considerable flexibility for specialist vehicle, commercial, recreational and auxiliary-power installations.

⚠️ IMPORTANT: The converter must be correctly programmed for the actual source voltage and service-battery voltage before operation.

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⚡ 50A MODEL

The product designation identifies this converter as the 50A version.

The supplied information also states that actual output current is determined by several factors:

• Maximum charge-current setting
• Maximum input-current setting
• Maximum operating-temperature limit of the converter

This means the actual charging current available in an installation can be lower than the nominal model designation depending on how the converter is programmed and the conditions under which it is operating.

⚠️ IMPORTANT: The supplied information does not include a detailed electrical specification table confirming continuous, peak or temperature-dependent current ratings. Where exact current capability is critical, refer to the current manufacturer technical documentation for this exact 50A model.

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🚦 BUILT-IN ENGINE-RUNNING DETECTION

The Buck-Boost includes an engine-running detection system.

This is designed to help avoid deep discharge of the vehicle's starting battery by controlling when the DC-DC converter is permitted to operate.

This functionality is especially useful in smart-alternator vehicles where the vehicle-system voltage does not necessarily provide a simple indication of whether the alternator is actively charging.

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🎛️ PROGRAMMABLE ALTERNATIVE ACTIVATION

Instead of using the built-in engine-running detection system, the converter can also be activated using a programmable input.

The supplied information lists the following possible activation methods:

• D+ signal
• CAN bus*
• (+)15 connection

This provides additional installation flexibility when the converter needs to be integrated with a suitable vehicle-control circuit.

⚠️ IMPORTANT: The supplied source references CAN bus with an asterisk but does not provide the associated compatibility note. Do not assume the converter can simply be connected directly to any vehicle CAN network. Refer to the applicable Victron installation documentation.

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💻 FULLY PROGRAMMABLE BY PC

The Buck-Boost converter can be configured using a dedicated PC application according to the supplied product information.

This allows important operating parameters to be tailored to the actual vehicle and battery installation rather than relying on one fixed configuration.

Programming requires:

USB Type-A male to USB Type-B male cable

⚠️ IMPORTANT: The supplied information states that this cable is required but does not state that it is included with the converter.

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⚡ PROGRAMMABLE CHARGE-CURRENT LIMIT

The maximum charge-current setting is one of the primary factors controlling the converter's output.

This allows the charging current to be configured around the requirements of the auxiliary battery and the overall electrical system.

⚠️ IMPORTANT: Battery charge-current limits vary by battery type, capacity, BMS and manufacturer. Do not automatically configure the converter for its maximum available current without checking the battery requirements.

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🔌 PROGRAMMABLE INPUT-CURRENT LIMIT

The converter also allows the maximum input current to be limited.

This is useful when the source electrical system has a specific current limitation or where alternator capacity needs to be managed alongside the vehicle's existing electrical loads.

Factors to consider can include:

• Alternator capacity
• Vehicle's existing electrical demand
• Input cable size
• Cable length and voltage drop
• Starter-battery condition
• Required auxiliary-battery charging rate

⚠️ IMPORTANT: The converter's input-current setting should be selected as part of the complete vehicle electrical-system design rather than in isolation.

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🌡️ TEMPERATURE-DEPENDENT OUTPUT

The supplied product information states that maximum operating temperature is another factor determining the converter's available output current.

This means charging current may be reduced if the converter approaches its thermal operating limit.

Correct mounting and adequate ventilation are therefore important, particularly with a high-current 50A converter.

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💡 INPUT STATUS LED INDICATION

The converter includes colour-coded input-status indication.

🟢 Green – Converter On
Indicates that the converter is operating.

🟡 Yellow – Input Voltage Below Threshold
The converter is off because the input voltage is below the required threshold.

🔴 Red – Over Temperature
The converter is off because an over-temperature condition has been detected.

🔵 Blue – Quick Flash
Engine running has been detected and the converter will start after the preset delay.

🔵 Blue – Slow Flash
The converter is off and activation is blocked because the input voltage is too low.

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💡 OUTPUT STATUS LED INDICATION

The output-side LED provides information about converter operation and service-battery voltage condition.

🟢 Green – Converter Off / Battery Voltage Normal
The converter is off and the battery voltage is considered normal according to the supplied status description.

🟡 Yellow – Converter Off / Battery Voltage Low
Indicates that the converter is off and the service-battery voltage is low.

🔴 Red – Battery Discharged or Not Connected
Indicates that the converter is off and the battery is discharged or not connected.

🟣 Purple – Converter On
Indicates that the converter is operating.

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🔋 CONTROLLED SERVICE-BATTERY CHARGING

The Buck-Boost is designed specifically around vehicle auxiliary-battery charging.

Rather than relying directly on whatever voltage the smart alternator happens to be producing, the converter applies a configured charging voltage to the service battery.

This allows the auxiliary-battery charging system to operate more predictably despite the changing behaviour of the vehicle's intelligent alternator.

⚠️ IMPORTANT: The supplied information does not specify exact charging profiles or battery-chemistry settings. Configure the converter according to the service-battery manufacturer's requirements and the applicable Victron instructions.

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🔋 HELPS PREVENT STARTER BATTERY DISCHARGE

The built-in engine-running detection system is specifically intended to help avoid deep discharge of the vehicle's starting battery.

By controlling when the converter becomes active, auxiliary-battery charging can be prevented when the vehicle's source system is not in a suitable operating state.

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🚙 4WD & TOURING APPLICATIONS

The Buck-Boost may suit compatible 4WD and touring vehicles requiring higher-current auxiliary-battery charging where the vehicle uses an intelligent alternator.

Potential applications include compatible:

• 🔋 Auxiliary battery systems
• 🏕️ Touring electrical systems
• ❄️ Fridge and accessory battery systems
• ⚡ High-demand 12V auxiliary installations
• 🔌 24V service-battery systems from compatible vehicle sources

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🚐 CAMPERVAN & MOTORHOME APPLICATIONS

The ability to configure both source and auxiliary-battery voltage can make the converter useful in compatible campervan and motorhome electrical systems where alternator charging forms an important part of the service-battery charging strategy.

The programmable input-current limit can also assist in configuring the charging system around the capability of the vehicle's alternator and wiring.

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🚚 COMMERCIAL & SPECIALIST VEHICLES

The converter may also suit compatible commercial vehicles, service vehicles and specialist installations requiring a programmable service-battery charging solution.

Potential applications can include:

• 🚚 Commercial vehicles
• 🚑 Service and emergency vehicle auxiliary systems
• 🛠️ Mobile workshops
• 🏗️ Machinery and mobile equipment
• 📡 Communications systems
• 🔋 High-demand auxiliary battery installations

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⚡ HIGHER-CURRENT 50A CHARGING PLATFORM

Compared with lower-current Buck-Boost models, the 50A product designation makes this unit relevant to systems requiring greater charging capability.

Higher charging current can reduce recharge time where the battery, alternator, wiring and installation are all capable of supporting it.

⚠️ IMPORTANT: Higher charging current also places greater demand on the alternator, source wiring and battery system. Confirm every part of the installation is rated appropriately.

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📋 PRODUCT INFORMATION SUMMARY

Product: Victron 12V/24V 50A Buck-Boost DC/DC Converter

Product type: Programmable vehicle DC-DC service-battery charging converter

Product designation: 50A

Service-battery voltage: Programmable for compatible 12V or 24V systems

Alternator / starter-battery system: Programmable for compatible 12V or 24V systems

Smart alternator support: Yes – according to supplied product information

Regenerative-braking applications: Yes

Euro 5 / Euro 6 applications: Yes

Engine-running detection: Built in

Alternative programmable activation: D+, CAN bus* or (+)15 connection according to supplied information

PC programmable: Yes

Programming cable required: USB Type-A male to USB Type-B male

Maximum charge-current setting: Programmable

Maximum input-current setting: Programmable

Temperature-dependent output limitation: Yes

Input-status LED: Yes

Output-status LED: Yes

⚠️ SPECIFICATION NOTE: The supplied information does not include a complete electrical specification table for this exact 50A model. Exact dimensions, weight, voltage ranges, terminal arrangement, IP rating and detailed continuous/peak current specifications have therefore not been added.

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⚠️ HIGH-CURRENT INSTALLATION CONSIDERATIONS

A 50A-class DC-DC charging system is a substantial electrical installation and requires correctly designed wiring and protection.

Key considerations include:

• Vehicle alternator capacity
• Starter-battery condition
• Auxiliary-battery maximum charging current
• Battery chemistry and charging requirements
• Input-current setting
• Charge-current setting
• Input cable size and length
• Output cable size and length
• Voltage drop
• Correct fuse or circuit-breaker protection
• Quality cable terminations
• Installation ventilation
• Correct engine-running detection or activation configuration

⚠️ IMPORTANT: The supplied information does not nominate cable sizes or fuse ratings. These should be calculated for the actual installation and configured current limits.

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⚠️ INSTALLATION & COMPATIBILITY CHECKLIST

Before purchasing or installing the Victron 12V/24V 50A Buck-Boost DC/DC Converter, confirm the requirements of the complete vehicle and auxiliary-battery system.

• Vehicle source voltage confirmed
• Service-battery nominal voltage confirmed
• Smart-alternator behaviour identified
• Battery charging requirements confirmed
• Battery maximum charging current confirmed
• Vehicle alternator capacity considered
• Existing vehicle electrical demand considered
• Maximum charge-current setting configured correctly
• Maximum input-current setting configured correctly
• Correct input and output cable sizing
• Appropriate circuit protection
• Correct engine-running detection setup
• Correct programmable activation input where used
• Suitable PC programming connection available
• Adequate ventilation and mounting space
• Correct polarity confirmed before connection

⚠️ IMPORTANT: Smart-alternator behaviour varies between vehicle manufacturers and models. Confirm the vehicle electrical architecture before installation.

⚠️ IMPORTANT: Do not automatically set the converter to its maximum charging current. Confirm the service battery, alternator, wiring and protection can safely support the selected current.

⚠️ IMPORTANT: The correct charging voltage depends on the battery chemistry and manufacturer's requirements. Program the converter accordingly.

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❓ FREQUENTLY ASKED QUESTIONS

What is the Victron 12V/24V 50A Buck-Boost Converter designed for?

It is designed for charging compatible 12V or 24V service batteries from vehicle electrical systems, including vehicles fitted with intelligent or smart alternators.

Is this the 50A model?

Yes. The supplied product designation identifies this version as the 50A Buck-Boost DC/DC Converter.

Will it always charge at 50A?

Not necessarily. The supplied information states that output current is determined by the maximum charge-current setting, maximum input-current setting and the converter's maximum operating-temperature limit.

Why is a DC-DC converter needed with a smart alternator?

Smart alternators can significantly vary their output voltage while the vehicle is operating. The Buck-Boost regulates this changing supply into a controlled charging voltage for the auxiliary battery.

Does it work with Euro 5 and Euro 6 vehicles?

The supplied product information specifically identifies Euro 5 and Euro 6 engine applications, including vehicles using regenerative-braking strategies.

Does every Euro 5 or Euro 6 vehicle use the same charging system?

No. Vehicle charging strategies vary by manufacturer, model and configuration. Confirm the actual vehicle electrical system before installation.

What does Buck-Boost mean?

It describes the converter's ability to regulate the charging output when the source voltage may be either higher or lower than the voltage required by the service battery.

Can it charge a 12V auxiliary battery?

Yes. The supplied information states that the converter can be programmed for a compatible 12V service-battery system.

Can it charge a 24V auxiliary battery?

Yes. It can also be programmed for a compatible 24V service-battery system according to the supplied information.

Can it operate from a 12V vehicle?

Yes. The supplied information states that it can operate from a compatible 12V alternator and starter-battery system.

Can it operate from a 24V vehicle?

Yes. It can also be configured for a compatible 24V source system.

Can it charge a 24V battery from a 12V vehicle?

The supplied information states that a 24V auxiliary battery can be charged from either a 12V or 24V alternator and starter-battery system when correctly configured.

Can it charge a 12V battery from a 24V vehicle?

Yes. The supplied information states that it can also be configured to charge a 12V auxiliary battery from a compatible 24V source system.

How does it know when the engine is running?

The converter incorporates a built-in engine-running detection system.

Why is engine-running detection important?

It helps prevent unnecessary deep discharge of the vehicle's starting battery by controlling when auxiliary-battery charging is permitted.

Can I use an ignition or D+ signal instead?

The supplied information states that the converter can alternatively be activated through a programmable D+, CAN bus* or (+)15 connection.

Can it connect directly to any vehicle CAN bus?

Do not assume this. The supplied source references CAN bus with an asterisk but does not include the associated compatibility details. Refer to the current Victron installation documentation.

Can the converter be programmed?

Yes. The supplied information states that it is fully programmable using a PC application.

What cable is needed for programming?

A USB Type-A male to USB Type-B male cable is required according to the supplied information.

Is the USB cable included?

The supplied information states that the cable is needed but does not state that it is included.

Can I limit the charging current?

Yes. The maximum charge-current setting is one of the factors used to determine output current.

Can I limit how much current it takes from the alternator?

Yes. The supplied information states that a maximum input-current limit can be configured.

Why would I reduce the input-current limit?

It may be necessary to manage demand on the alternator, source wiring or vehicle electrical system depending on the installation.

Does temperature affect charging current?

Yes. The supplied information states that the converter's maximum operating-temperature limit is one of the factors determining available output current.

What does a green input LED mean?

Green indicates that the converter is on.

What does a yellow input LED mean?

Yellow indicates that the input voltage is below the required threshold and the converter is off.

What does a red input LED mean?

Red indicates that an over-temperature condition has occurred and the converter is off.

What does a rapidly flashing blue input LED mean?

It indicates that engine running has been detected and the converter will start after the preset delay.

What does a slowly flashing blue input LED mean?

It indicates that the converter is off and activation is blocked because the input voltage is too low.

What does a green output LED mean?

According to the supplied information, green means the converter is off and the service-battery voltage is normal.

What does a yellow output LED mean?

Yellow means the converter is off and the service-battery voltage is low.

What does a red output LED mean?

Red means the converter is off and the service battery is discharged or not connected.

What does a purple output LED mean?

Purple indicates that the converter is on.

Can I use this with an AGM battery?

The supplied information confirms programmable service-battery charging but does not provide AGM-specific charging parameters. Confirm the battery manufacturer's charging requirements and configure the converter accordingly.

Can I use this with a lithium battery?

The supplied information does not specifically confirm lithium compatibility or provide lithium-specific charging settings. Confirm the exact battery, BMS requirements and current Victron documentation before installation.

Will 50A charging suit every auxiliary battery?

No. Maximum permitted charging current varies significantly between batteries. Confirm the battery manufacturer's maximum and recommended charge-current specifications before configuring the converter.

Will my alternator support a 50A converter?

This depends on alternator output, vehicle electrical demand, operating conditions and converter configuration. Alternator capacity should be assessed before installation.

What cable size should I use?

The supplied information does not nominate a cable size. Input and output cable should be calculated according to configured current, cable length, voltage drop and installation conditions.

What fuse size should I use?

The supplied information does not specify fuse ratings. Circuit protection should be selected according to the actual configured current, cable capacity and complete system design.

Does it protect the starter battery?

The built-in engine-running detection system is specifically intended to help prevent deep discharge of the vehicle's starting battery.

Can I use this in a 4WD?

Potentially. It may suit compatible 4WD auxiliary-battery systems, particularly where a smart alternator is fitted and higher charging current is required.

Can I use it in a campervan?

Potentially. Its programmable 12V/24V operation and smart-alternator compatibility can make it suitable for compatible campervan service-battery systems.

What should I check before ordering?

Confirm the vehicle source voltage, service-battery voltage, smart-alternator behaviour, battery chemistry and charging requirements, alternator capacity, desired charging current, input-current limit, control method, cable requirements and circuit protection before purchase.

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⚡ HIGH-CURRENT SMART-ALTERNATOR CHARGING FOR 12V & 24V VEHICLE SYSTEMS

The Victron 12V/24V 50A Buck-Boost DC/DC Converter provides a highly configurable solution for demanding vehicle auxiliary-battery systems where traditional alternator charging is no longer sufficient.

With smart-alternator support, Buck-Boost voltage control, 12V and 24V system flexibility, built-in engine-running detection, programmable D+ / CAN bus* / (+)15 activation, PC configuration, charge-current control and input-current limiting, it provides the flexibility required for a wide range of modern vehicle and specialist auxiliary-power installations.

For a 50A-class charging installation, correct programming, battery compatibility, alternator capacity, cable sizing and circuit protection are particularly important. Confirm the complete electrical-system requirements before installation to ensure the converter is correctly configured for the vehicle and auxiliary battery.