ChargeMaster 3 Bank Battery Charger 12 volt 35 amp

The Mastervolt ChargeMaster Plus 12/35-3 is an all-in-one 12 V battery charger designed for faster, safer, and more flexible charging in marine, mobile, recreational, and semi-professional power systems. With three battery outlets and automatic power distribution, it can charge almost any combination of two or three batteries while distributing charging current based on each battery’s condition.

Its “Battery’s Best Friend” architecture supports multiple battery chemistries using Mastervolt’s fast and safe 3-step+ charging method. Pre-float functionality helps reduce the risk of overcharging smaller batteries, while the included Lithium Ion profile and user-defined charging option provide flexibility for modern battery systems.

The ChargeMaster Plus 12/35-3 can operate as a standalone plug-and-play charger or as part of a complete MasterBus or CZone system. It is built for harsh marine and mobile environments, with galvanic isolation, vario fan cooling, wide AC input compatibility, high-temperature operation, and multiple safety protections.

Key Features

• 12 V battery charger with 35 A total charge current
• Three battery outlets for charging multiple battery banks
• Automatic 3-step+ charging for Gel, AGM, flooded, and Lithium Ion batteries
• User-defined charging profile option
• Automatic current distribution based on battery condition
• All three outputs can provide maximum current, as long as total output does not exceed the model maximum
• Pre-float functionality helps prevent overcharging smaller batteries
• Compatible with worldwide mains voltages and frequencies
• Can be used as a standalone charger or integrated into a complete system
• MasterBus, CZone, and NMEA2000 communication interfaces
• Can communicate with Mastervolt Lithium Ion batteries, MasterShunt, or system display for real-time adjustments
• Improved cooling technology for low noise across the power range
• Power supply mode
• Galvanic isolation
• LED display
• Smaller and lighter than the previous model

Technical Specifications

• Product code: 44310355
• Nominal output voltage: 12 V
• Maximum output current, primary output: 35 A
• Total charge current: 35 A at 14.25 V
• Maximum AC current at 230 V / 120 V: 2.5 A / 5.0 A
• Number of battery outlets: 3 maximum
• Battery bank size: 140-350 Ah
• Nominal input voltage: 120/230 V AC, 80-275 V, 50/60 Hz
• Power supply mode: Yes
• Galvanic isolation: Yes
• Display/read-out: LED display
• Dimensions: 291 x 210 x 105 mm / 11.5 x 8.3 x 4.1 in
• Weight: 2.5 kg / 5.5 lb
• Communication interfaces: MasterBus, CZone, NMEA2000
• Charge characteristic: IUoUo, automatic / 3-step+ for Gel, AGM, flooded, Lithium Ion, plus user-defined option
• Temperature compensation: -30 mV/°C / -38 mV/°F, including temperature sensor
• DC voltage compensation: Yes, via automatic compensation or MasterShunt
• DC-side power consumption: Less than 2 mA with MasterBus off
• Current Control function: Yes, through MasterBus or CZone
• Power factor control: Greater than 0.98
• Ambient temperature range: -25°C to 70°C
• Derating: Above 40°C; 80% power at 60°C
• Cooling: Vario fan
• Protection degree: IP23, vertical mounting
• Charger Status Interface: Yes, using Multipurpose Contact Output, code 77030500
• Compliance: CE, CEC, DOE, ABYC, UL1236, cULus, SAE J1171, ISO 8846, ACMA

Applications

• Marine battery charging systems
• RV and mobile power systems
• Multi-bank 12 V battery charging
• Harsh maritime and mobile environments
• MasterBus-integrated electrical systems
• CZone-integrated electrical systems
• NMEA2000-connected power systems
• Lithium Ion battery charging systems
• Shore power and generator-supported charging systems

Ideal For

• Boat owners needing a compact multi-bank 12 V charger
• RV owners charging multiple battery banks
• Installers building MasterBus, CZone, or NMEA2000 power systems
• Users combining different battery sizes
• Systems using Gel, AGM, flooded, or Lithium Ion batteries
• Applications needing automatic charging current distribution
• Harsh marine or mobile environments with voltage fluctuations or high temperatures

Protection Features

• Over-temperature protection
• Overload protection
• Short-circuit protection
• High battery voltage protection
• Low battery voltage protection
• Ignition protection
• Pre-float functionality to help prevent overcharging smaller batteries
• Galvanic isolation

System Compatibility

• Compatible with 12 V battery systems
• Compatible battery types: Gel, AGM, flooded, and Lithium Ion
• User-defined charging profile option for customized battery charging
• Recommended battery bank size: 140-350 Ah
• Supports up to three battery outlets
• Compatible with 120/230 V AC input, 80-275 V, 50/60 Hz
• Communication interfaces: MasterBus, CZone, NMEA2000
• Current Control available through MasterBus or CZone
• DC voltage compensation available automatically or through MasterShunt
• Can communicate with Mastervolt Lithium Ion batteries, MasterShunt, or system display
• Suitable for standalone plug-and-play use or complete integrated systems

Check Before Ordering

• Confirm your system uses a 12 V battery bank.
• Confirm your battery bank size is within the recommended 140-350 Ah range.
• Confirm the 35 A total charge current is suitable for your batteries and charging requirements.
• Verify battery chemistry and charging profile requirements before installation.
• For Lithium Ion batteries, confirm system configuration and communication requirements.
• Confirm whether your installation requires MasterBus, CZone, or NMEA2000 integration.
• Confirm vertical mounting is suitable for the installation location and IP23 protection rating.
• Allow for derating in high-temperature environments above 40°C.
• Confirm available AC input power and compatibility with 80-275 V AC, 50/60 Hz.
• Verify available mounting space for the 291 x 210 x 105 mm unit dimensions.
• Confirm whether the optional Charger Status Interface contact output is required for alarm integration.