Mastervolt Alpha III Pro Charge Regulator

Advanced 3-step charge regulator for standard and high performance alternators

The propulsion engine of your boat or vehicles may be used to quickly charge your service batteries, either while cruising or taking a break. The advanced and powerful Alpha Pro III ensures fast and safe charging, protecting both the engine and the batteries. Building on 10 years of experience, the Alpha Pro III features a modernized look, higher power and improved ease of use.

The Alpha Pro III measures the temperature and the voltage of your batteries to prevent overcharging, keeping them in perfect condition. It also monitors the engine load, thus reducing sound variations, wear and tear. The smart ‘keep alive' feature solves a common problem causing unreliable tachometer readings. Via MasterBus, it communicates RPM, alternator status and charge status to create intelligent power systems.

Pull the max out of your alternator

The alternator that comes with the engine is not optimally suited for charging service batteries. Designed for low cost and short charge cycles, it charges at a slow pace and is easily overheated. Replacing the standard regulator (not allowed on Euro 5/6 engines) with the Alpha Pro III optimizes this charging process, protects against overheating and overcharging and extends the lifetime of your batteries.

Super charge your system

For superfast charging at low RPM, Mastervolt recommends to combine the Alpha Pro III with a high performance alternator such as the reputable Alpha series. With 20 amps of field current capability, the Alpha Pro is the only 3-step regulator in the market capable of controlling alternators with outputs up to 400 A!

Alpha Pro III: Fast charging, anytime, anywhere.

Features

• Transforms every alternator into a full temperature controlled 3-step charger
• Reduces run time, saves fuel, reduces noise and emissions
• Protects from overcharging and extends battery life
• Balances engine load, reducing RPM variations
• Compatible with standard and high performance alternators, include 200 A ~ 400 A models
• Integrated ‘keep alive' feature for reliable tachometer readings
• Suitable for every battery type, including Lithium Ion
• Suitable for 12 V and 24 V system voltages
• MasterBus compatible: simplifies wiring, saves space and weight, and creates optimal cooperation between Mastervolt products

Applications

Applications range from improving the performance of a standard alternator in a vehicle or boat, to generator replacement, when combined with a high performance alternator.

General Specifications

• Link to MasterShunt: Yes
• Connection to Mastervolt alternator: Yes
• Connection to Bosch alternator: Yes, using a Bosch adapter cable (product code 45510500))
• Nominal battery voltage: 12 V/24 V
• Cable length regulator/alternator: 1.5 m/5 ft oil resistant connection cable
• Connection plug regulator/alternator: Alpha/Mastervolt
• Cooling: Fanless
• MasterBus powering: Yes
• Display/read-out: LED display
• Dimensions (H x W x D): 90 mm (3.5") x 109 mm (4.3") x 30 mm (1.2")
• Weight: 0.4 kg
• Delivered with: Battery temperature sensor with 6 m (20 ft) cable
• Approvals: CE

Technical Specifications

• Charge characteristic: IUoUo, automatic/3-step+ for Gel/AGM/flooded/Lithium Ion
• Charge voltage bulk/absorption/float: Default setting for AGM, Gel and Lithium Ion (adjustable)
• Absorption time: 4 hours, adjustable from 2 minutes to 12 hours
• Temperature compensation: -30 mV/°C/-17 mV/°F
• DC voltage compensation: Voltage drop compensation in DC cables up to 3 V
• Alternator type: Alternators with negative excitation
• Field currents: Up to 20 A
• MasterBus compatible: Yes

Optional Extra

1. Bosch Adapter Cable MV45510500

2. Alternator Temperature Sensor MV41500400

Technical Files

Product Notifications
User Manual
Installation Manual