Alpha Pro MB

The charge regulator measures the battery temperature and adjusts the charging process accordingly, resulting in a safe and fast charge. Therefore the battery is always kept in good condition.

  • Suitable for 12 and 24 V.
  • Including plug & play connection cable, an adapter cable for Bosch alternators is optional.
  • The Alpha Pro MB is suitable for alternators up to 200 amps.
  • Automatic voltage and temperature compensation.
  •  ‘Keep alive’ function for tachometer.
  • MasterBus compatible.

Alpha Pro: Easy to operate

Easy operation LEDs on the body of the charge regulator indicate the charge phase. The Alpha Pro is designed as a ‘fit all’ solution. Just one unit is needed for both 12 and 24 V applications, with a simple selector switch to set the regulator to the right voltage. The charge regulator can also be used on any other brand of alternator that has a standard Bosch connector, using a Bosch adapter cable (optional; product code 45510500). 

MasterBus connectivity

The Alpha Pro is compatible with MasterBus, allowing easy monitoring via a MasterView touchscreen. In a MasterBus system the voltage drop over the battery cable and the battery temperature is compensated automatically.

Benefits of a Mastervolt charge regulator

  • The Alpha Pro charge regulator maximises the output of Mastervolt Alpha alternators or any other alternator by regulating the alternator in a way that the batteries receive the optimum charge. The proven 3-step+ charge method used by all Mastervolt battery chargers guarantees fast and safe charging of your batteries.
  • The Alpha Pro helps to cut emissions by requiring less run time because it maximises the power from any alternator. A battery can be charged quickly even at very low RPM, especially when connected to an Alpha series alternator. By connecting the Alpha Alternator to a Battery Mate or battery isolator, several battery banks can be charged simultaneously.
  • Does your tachometer sometimes indicate zero while the engine is running? The ‘keep alive’ function of the Alpha Pro gets rid of this problem for ever.

Product code: 45512000 This product is no longer available.
Please click here for the current model:
Alpha Pro III
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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 mtr oil resistant connection cable
Connection plug regulator/alternator Alpha/Mastervolt
Cooling fanless
MasterBus powering yes
Display/read-out LED display
Dimensions, hxwxd 90 x 109 x 30 mm
3.5 x 4.3 x 1.2 inch
Weight 0.4 kg
0.9 lb
Delivered with accutemperatuursensor met 6 mtr (20 ft) kabel
Approvals CE
Technical specifications
Charge characteristic IUoUo, automatic / 3-step+ for gel/AGM/wet/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 to 10 Ampère
MasterBus compatible yes



Alpha Pro MB

EU DoC Alpha Pro


Installation manuals

Alpha Pro MB

Appendix Alpha Pro Alternator (English)


User manuals

Alpha Pro MB

User's manual Alpha Alternator and Alpha Pro regulator (English)


3D product drawings

3D-drawing Alpha Pro regulator (zipped STEP file)



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