Littelfuse FLNR 35 FLNR035 Fuse

The Littelfuse FLNR 35 is a high-performance Class RK5 time-delay fuse engineered for heavy-duty industrial and HVACR applications. Rated for 35 Amps at 250 VAC and 125 VDC, this dual-element cartridge fuse is specifically designed to handle the high inrush currents typical of motors, transformers, and industrial solenoid circuits. The FLNR035 provides superior protection by allowing temporary surges without nuisance tripping, while maintaining a high 200,000A AC interrupting rating to safely clear massive fault currents. As a current-limiting fuse, it significantly reduces the destructive thermal and magnetic forces that can damage downstream equipment during a short circuit. This Slo-Blo/Time Lag fuse is a standard choice for service entrance equipment and branch circuit protection where reliability and precision are critical for maintaining system uptime and protecting expensive hardware.

Key Benefits

• Dual-Element Design: Provides a massive time-delay to prevent unnecessary shutdowns during motor startups and inductive load surges.
• High Interrupting Capacity: Rated for up to 200,000 Amps AC, ensuring robust circuit protection in systems with high available fault currents.
• Current-Limiting Performance: Fast-acting response during short-circuit conditions limits peak let-through current to protect sensitive components.
• Versatile Voltage Rating: Safely operates in both 250V AC and 125V DC (20kA interrupting) environments for broad technical compatibility.
• Industrial Cartridge Construction: Standardized form factor ensures easy integration into existing fuse blocks and disconnect switches for 35A fused protection.

Common Questions

What is the difference between FLNR and FLSR fuses?
The Littelfuse FLNR035 is a 250V rated fuse, whereas the FLSR series is rated for 600V. Both are Class RK5 and feature time-delay characteristics, but they must be matched to the specific system voltage of your installation.

Can I use an RK5 fuse in an H or K5 fuse block?
Yes, Class RK5 fuses like the FLNR 35 will fit into Class H or K5 fuse clips. However, those clips will not accept an RK1 fuse, making the RK5 a versatile choice for upgrading older equipment protection profiles.

Why use a time-delay fuse for HVACR compressors?
Compressors exhibit high "Locked Rotor Amps" (LRA) upon startup. A standard fast-acting fuse would blow instantly, while the Slo-Blo FLNR 35 permits this brief peak current before settling into its 35A continuous run rating.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.