Balmar 12V 240A 97XD Series Alternator, 4in Saddle Mount, K6 Pulley, Isolated Ground

High-Output 97XD Series 12V 240A Alternator for Heavy-Duty Power Generation

The 97XD Series 12V 240A Alternator is engineered to meet the electrical demands of modern marine vessels and other large diesel applications. Delivering a substantial 240A output at 12V, this heavy-duty unit provides the amperage required to rapidly charge large battery banks, including high-capacity lithium (LiFePO4) and AGM systems. Unlike standard automotive alternators that struggle under sustained high-load conditions, the Extra-Large Case 97XD Series is designed for extended-duty operation.

Precision Mounting and Belt Drive Integration

Designed for secure mechanical integration, this model features a robust 4in (Approx. 101.6mm) dual foot saddle mount. This J-180-style mounting provides stability and alignment on compatible engine brackets, reducing vibration-related wear. Power transfer is handled by a fitted K6 (6-groove serpentine) pulley, which maximises belt grip and minimises slippage when the alternator is under heavy load, preventing premature belt degradation and ensuring consistent charging performance.

Isolated Ground Architecture for Enhanced Safety

A critical feature of the B-97XD-12-240-IG is its Isolated Ground (IsoGrd) design. In standard case-grounded alternators, the engine block serves as the return path for electrical current. For marine applications—particularly on aluminium, steel, or composite hulls—stray current through the engine block can accelerate galvanic corrosion and damage expensive underwater hardware. An isolated ground alternator provides a dedicated negative terminal, keeping the electrical circuit completely separate from the engine block and chassis. This significantly reduces the risk of stray current corrosion.

Key Features and Benefits

• High 240A Output at 12V: Delivers rapid bulk charging for large house battery banks and supports high-draw DC appliances simultaneously.
• 4in (Approx. 101.6mm) Saddle Mount: Provides a secure J-180-style fitment on compatible engine brackets.
• Isolated Ground (IsoGrd) Terminal: Reduces the risk of stray current corrosion in marine environments and ensures clean, isolated return paths for complex dual-battery electrical systems.
• K6 Serpentine Pulley: Multi-ribbed 6-groove pulley design handles high torque loads efficiently, reducing belt slip during peak amperage generation.
• Extended-Duty 97XD Design: Extra-Large Case with braided-stator technology for strong output at low RPM.

Built to Solve High-Demand Charging Challenges

Upgrading to a high-capacity battery bank often exposes the limitations of factory-fitted alternators, which can overheat and fail when subjected to the low internal resistance of lithium batteries. The 97XD Series is specifically designed to bridge this gap. By pairing this unit with an appropriate external voltage regulator (required, sold separately), users can program precise multi-stage charging profiles tailored to their exact battery chemistry. This reduces engine run-time, saves fuel, and extends the operational lifespan of both the alternator and the energy storage system.

Ideal Applications

• Cruising yachts, commercial workboats, and marine vessels requiring isolated ground protection
• Large diesel engines servicing extensive 12V house battery loads

Upgrade Your Charging System

Equip your vessel or large diesel engine with the 97XD Series 240A 12V Alternator to ensure dependable, high-amperage power generation whenever your engine is running. Review your engine mounting dimensions and belt configuration to confirm compatibility, and integrate this heavy-duty alternator into your electrical system today.