Mastervolt 48512090 Wiring Harness Alpha Pro 2

Mastervolt Wiring Harness for Alpha Pro 2 / Alpha Pro II Charge Regulator

The Mastervolt 48512090 is a pre-wired, marine-grade installation cable harness and temperature sensor assembly manufactured specifically for the legacy Mastervolt Alpha Pro 2 (Alpha Pro II) 3-stage advanced external alternator regulator. Engineered to establish a clean interface between high-output alternators (such as the Mastervolt Alpha series or compatible third-party alternators) and the Alpha Pro 2 regulation unit, this harness streamlines engine room installation while protecting against wiring errors.

The harness features color-coded, oil- and flame-retardant tinned copper conductors terminated with a quick-connect multi-pin plug for the regulator body, along with pre-crimped terminal lugs, integrated field fusing, and a $6\text{ m}$ ring-terminal battery temperature sensor. This allows the Alpha Pro 2 regulator to continuously adjust alternator output voltage based on battery temperature, ensuring maximum battery lifespan and rapid charge cycles.

Delivery includes Alpha Pro MB charge regulator.

• Fast & complete charging of starter and service batteries.
• Power supply for all consumers.
• 12 V and 24 V versions.
• 75 A to 150 A charge current.
• Standard delivered with Alpha Pro MB charge regulator for an optimal performance and longer-lasting batteries.

Using a Battery Mate or battery isolator in conjunction with an Alpha alternator makes it possible to easily charge two or three separate battery sets simultaneously.

TIP: A second alternator on the main engine, combined with a larger battery bank and inverter, could be an alternative for a generator.

Key Features

• Dedicated Alpha Pro 2 Interface: Plug-and-play multi-pin socket engagement eliminates custom terminal wiring and pinout mistakes.

• Integrated Temperature Sensor: Includes ring-terminal thermal probe for real-time temperature-compensated battery charging profiles.

• Tinned Marine Copper Conductors: Resists internal corrosion and oxidation under high engine room humidity and saltwater air exposure.

• In-Line Circuit Protection: Integrated ATC blade fuse assembly protects the regulator's field output driving circuit against shorts and overload.

Specifications