Overview
The 55SI is Delco Remy's most power-dense heavy-duty brushless alternator, packing up to 430A at 12V or 275A at 24V into a compact 8-inch frame weighing just 43 lbs (19.5 kg). Its brushless design eliminates wear-prone components for extended service life, while Remote Sense technology actively compensates for voltage drop to keep batteries fully charged. Available in both 12V and 24V configurations, the 55SI serves applications from long-haul trucks with auxiliary power units to heavy mining and construction equipment.
Key Features
- Brushless design for maximum reliability and minimum maintenance
- 12V up to 430A; 24V at 250A and 275A
- Compact 8-inch frame length, only 43 lbs (19.5 kg)
- Pad mount configuration; clockwise rotation
- Remote Sense — reduces battery charge time by up to 50%
- Dual internal fan (DIF) cooling for sustained output under extreme heat
- High efficiency reduces engine parasitic draw and improves fuel economy
Applications
- Long-haul trucks with auxiliary power units (APUs)
- Utility and work trucks with high electrical demand
- Fire trucks and emergency vehicles
- Wheel loaders, graders, and mining equipment (24V)
- Any heavy-duty application requiring maximum amperage in a compact package
