Sinofuse RS309-MD-250A High-Speed Fuse, 250A 500VDC, aR Bolt-on Bolt-down, 7ZB Size - Pack of 5

The Sinofuse RS309-MD-250A is a high-capacity, high-speed semiconductor fuse designed for superior circuit protection in power electronic systems. Engineered specifically for the electric vehicle (EV) industry, this fuse is widely utilized in battery management systems (BMS), power conversion units, DC charging stations, and motor controllers. It provides reliable short-circuit protection for rectifiers, thyristors, and other sensitive semiconductor components.

Key Features:

• Rapid Arcing Extinction: Specifically optimized with a specialized quartz sand filling for extremely low  (Intercalated time-current characteristics), ensuring minimal energy pass-through during faults.
• High Interrupting Capacity: Capable of clearing fault currents up to 50kA at 500VDC, maintaining system integrity under extreme conditions.
• Reliable Performance: Excellent resistance to cyclical thermal loading and mechanical vibrations, meeting the rigid requirements of ISO8820 and GB/T 31465 standards.
• International Safety Standards: Fully compliant with UL248, IEC60269, and TUV regulations. The product is CE and RoHS certified for global compatibility.

Technical Specifications:

• Manufacturer: Sinofuse (Xi'an Sinofuse Electric Co., Ltd.)
• Model: RS309-MD-250A
• Rated Voltage: 500VDC / 500VAC
• Rated Current: 250A
• Utilization Category: aR (High-speed semiconductor protection)
• Breaking Capacity: 50kA at 500VDC / 200kA at 500VAC
• Pre-Arcing I²t: 10,200 A²s
• Total Clearing I²t: 38,500 A²s (at 500V)
• Rated Power Loss: 44W
• Size Code: 7ZB
• Mounting Type: Bolt-on / Bolt-down (M10 Bolt)
• Recommended Torque: 21±1N.m
• Altitude Performance: Standard up to 2000m (derating required for higher altitudes)