FNQR-6 TIME DELAY FUSE BUSSMANN

FNQR-6 TIME DELAY FUSE BUSSMANN

FNQR-6 TIME DELAY FUSE BUSSMANN – Industrial 6A 600VAC Class CC Time-Delay Current-Limiting Fuse

The FNQR-6 TIME DELAY FUSE BUSSMANN (Model FNQ-R-6) is a high-performance, current-limiting Class CC time-delay power fuse manufactured by Eaton’s Bussmann series. Engineered specifically to provide advanced overcurrent protection for industrial control transformers, motor branch circuits, solenoids, and control panels, this 6-amp, 600 VAC LIMITRON™ fuse balances high-speed short-circuit interruption with surge-tolerant time-delay operation.

Featuring a dual-element design, the FNQR-6 TIME DELAY FUSE BUSSMANN delivers a minimum 12-second time-delay at 200% of its rated current. This extended delay enables high temporary magnetizing inrush surges from control transformers and startup spikes from small motors to pass without causing nuisance openings. Under severe fault conditions, its fast-acting current-limiting design interrupts high-energy short circuits up to 200 kA RMS Symmetrical at 600 VAC. Built with a physical Class CC rejection tip, it actively prevents lower-rated supplementary or non-rejection fuses from being inserted into protected circuits.

As shown in the image, the fuse features a high-density melamine body wrapped with a clear label reading “Bussmann LIMITRON™ CURRENT LIMITING TIME-DELAY CLASS CC FUSE FNQ-R-6 600Vac”, terminated on both ends with nickel-plated ferrule end caps and a rejection tip at the bottom end cap.

Key Features of the FNQR-6 TIME DELAY FUSE BUSSMANN

• Class CC Size Rejection Profile: Standardized Class CC rejection end tip physically keys into Class CC fuse holders, preventing over-fusing or substituting non-current-limiting devices.

• 12-Second Time-Delay Performance: Delivers a minimum 12-second time-delay at 200% current overload to absorb heavy startup inrush surges without premature tripping.

• High 200 kA Breaking Capacity: Rated to interrupt fault currents up to 200 kA RMS Symmetrical at 600 VAC, fulfilling National Electrical Code (NEC®) Section 110.9 safety requirements.

• Superior Current Limitation: Provides up to 10X better current limitation than standard non-current-limiting fuses, drastically restricting thermal (I^2t) and magnetic stress on downstream components.

• Compact 10.3 x 38.1 mm Size: Industry-standard 13/32” x 1-1/2” midget footprint allows high-density installation in space-restricted control enclosures.

• High-Strength Melamine Tube: Constructed with a high-grade melamine casing that offers high structural integrity and arc-quenching performance.

Common Applications and Practical Usage

The high breaking capacity and specialized surge tolerance of the FNQR-6 TIME DELAY FUSE BUSSMANN make it an ideal choice across industrial machinery and panelboard platforms:

• Control Transformer Primary Protection: Protects primary circuits of industrial control transformers against short circuits while handling magnetizing inrush surges.

• Small AC Motor Branch Circuits: Serves as branch-circuit protection for fractional horsepower motors, blowers, and motor controllers.

• Solenoid & Contactor Coils: Prevents coil burnout in industrial solenoids, electromagnetic valves, and contactors.

• Industrial Automation & Control Panels: Protects auxiliary feeders, power supplies, and control loops in 600V machine control cabinets.

Technical Specifications

The core electrical, physical, and compliance parameters for the FNQR-6 TIME DELAY FUSE BUSSMANN are detailed below:

Operating Guidelines and Usage Tips

SAFETY NOTICE: Always isolate power supplies and verify circuits are fully de-energized using a calibrated voltage tester prior to inspecting or replacing fuses.

• Holder Compatibility: Install exclusively in dedicated UL Class CC rejection fuse blocks or finger-safe DIN-rail holders (such as Bussmann CHCC series holders) to ensure proper rejection pin engagement.

• Transformer Sizing: Size fuses according to NEC® Article 450 guidelines for primary control transformer protection to accommodate magnetizing inrush while ensuring short-circuit protection.