Sinofuse RS309-MD High-Speed Bolts Fuses | AC/DC 500V (35A-1200A)

The Sinofuse RS309-MD Series represents a premier line of cylindrical bolted high-speed fuses designed to protect highly sensitive semiconductor components and high-energy battery infrastructures. Combining a highly compact form factor with ultra-low melting I²t values, these fuses strictly limit passing thermal energy during fault conditions, ultimately preventing catastrophic damage to high-value switching components.

Product Overview

Engineered for absolute performance reliability in electrified transport and industrial energy applications, the RS309-MD series features an operating rating of 500V AC/DC and a scalable current range spanning from 35A to 1200A. Classified under the aR operating class, these high-speed fuses deliver an impressive interrupting rating of up to 200kA AC and 50kA DC. They are rigorously tested to withstand aggressive chemical loads, severe vibration (Railway Class II and road vehicle tracking standards), and wide temperature fluctuations (-40°C to 120°C).

Typical Applications

• Electric Vehicle (EV) Powertrains: Short-circuit and overload protection for main drive systems and converters.
• Energy Storage Systems (ESS): Reliable, low-loss protection for high-capacity battery racks and power conditioning systems.
• Industrial Power Conversion: Protection for variable frequency drives (VFDs), inverters, and rectifiers.
• DC Fast Charging Infrastructure: Critical backup and fault protection for high-output EV charging stations.

Key Features & Benefits

• Ultra-Low Let-Through Energy (I²t): Rapidly isolates faults, minimizing thermal stress on downstream IGBTs, SCRs, and sensitive semiconductors.
• Superior Environmental Endurance: Operational stability from extreme cold (-40°C) up to severe high-heat environments (+120°C), adapting effortlessly to mobility applications.
• Robust Mechanical Integrity: Engineered to absorb heavy mechanical shock and vibration (meets GB2423.10-2008 and QC/T 413-2002).
• Global Standard Compliance: Manufactured in accordance with UL248, IEC 60269, and automotive safety standards (ISO8820, GB/T 31465).

Product Range & Selection Guide