FNQ-R-1/4 BUSSMANN FUSE
FNQ-R-1/4 BUSSMANN FUSE – Industrial 1/4A (0.25A) 600VAC Class CC Time-Delay Current-Limiting Fuse
The FNQ-R-1/4 BUSSMANN FUSE (Catalog Model FNQ-R-1/4) is an industrial-grade, Class CC high-inrush time-delay current-limiting fuse manufactured by Eaton’s Bussmann series. Engineered specifically to provide advanced overcurrent, short-circuit, and high-inrush protection for sensitive control transformers, industrial control circuits, solenoids, and low-amperage branch feeds, this 1/4-amp (0.25A), 600 VAC LIMITRON™ fuse combines high breaking capacity with a compact rejection profile.
Featuring specialized dual-element time-delay characteristics, the FNQ-R-1/4 BUSSMANN FUSE holds a minimum 12-second time-delay at 200% of its rated current. This extended delay enables high magnetizing inrush currents from primary control transformers and inductive start-up transients to pass without causing nuisance fuse openings. Under severe electrical fault conditions, its rapid current-limiting action safely interrupts prospective short-circuit currents up to 200 kA RMS Symmetrical at 600 VAC. Constructed in a compact 13/32” x 1-1/2” (10.3 x 38.1 mm) melamine body format, it incorporates a physical Class CC rejection tip on the bottom end cap to prevent non-current-limiting or lower-rated fuses from being improperly substituted.
Key Features of the FNQ-R-1/4 BUSSMANN FUSE
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High-Inrush Time-Delay Performance: Engineered with a minimum 12-second time-delay at 200% rated current, effectively eliminating nuisance fuse blowing caused by transformer energization inrushes.
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Class CC Physical Rejection Tip: Includes a standardized rejection end tab designed exclusively for UL Class CC rejection fuse blocks, preventing accidental over-fusing.
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High 200 kA Interrupting Rating: Rated to safely clear severe short-circuit currents up to 200 kAIC at 600 VAC, fully complying with NEC® Section 110.9 system requirements.
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Up to 10X Current Limitation: Restricts peak let-through thermal energy (I^2t) and magnetic forces during fault conditions, protecting sensitive control equipment and wiring.
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600VAC Continuous Rating: Provides maximum operating voltage capability for standard 480 V and 600 V industrial control cabinets and branch circuits.
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Compact Physical Footprint: Standardized 13/32” x 1-1/2” dimensions enable space-saving installation in high-density automated panelboards.
Common Applications and Practical Usage
The high interrupting capacity, precise 0.25A rating, and superior surge handling of the FNQ-R-1/4 BUSSMANN FUSE make it a protective device across industrial automation platforms:
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Control Transformer Primary Protection: Specially designed to protect primary circuits of small industrial control transformers without blowing during high initial magnetizing surges.
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Industrial Control Circuits: Safeguards sensitive low-amperage control wiring, PLC output channels, and electronic instrumentation from overloads.
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Solenoid Coils & Relays: Protects low-power inductive control solenoids, electromagnetic valves, and relay actuation lines.
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General Branch Circuit & Line Protection: Serves as dedicated primary or secondary branch circuit overcurrent protection in 600 V machinery cabinets.
Technical Specifications
The core electrical, physical, and compliance parameters for the FNQ-R-1/4 BUSSMANN FUSE are detailed below:
| Parameter Specification | Technical Details & Operational Values |
| Component Classification | Class CC Time-Delay Current-Limiting Branch Circuit Fuse |
| Primary Target Keyword | FNQ-R-1/4 BUSSMANN FUSE |
| Brand / Series | Eaton Bussmann Series / LIMITRON™ FNQ-R |
| Catalog Model / Part No. | FNQ-R-1/4 |
| Amperage Rating | 1/4 Amp (0.25A) |
| Voltage Rating | 600 VAC |
| Interrupt Rating (IR) | 200 kA RMS Symmetrical at 600 VAC (200 kAIC) |
| Response Characteristic | Time-Delay (Min. 12 seconds at 200% current) |
| Fuse Class & Form Factor | UL Class CC Rejection Ferrule (13/32” x 1-1/2” / 10.3 x 38.1 mm) |
| Terminal Connection Type | Ferrule End x Ferrule End with Rejection Tip |
| Body Material | Melamine Tube with Metal End Caps |
| Agency Certifications | UL Listed (Std 248-4, Class CC, Guide JDDZ, File E4273), CSA Certified, CE |
Operating Guidelines and Usage Tips
SAFETY NOTICE: Always isolate main power supplies and verify circuits are completely de-energized using a calibrated voltage tester prior to inspecting or replacing power fuses.
Holder Compatibility: Install exclusively in dedicated UL Class CC rejection fuse blocks or finger-safe modular DIN-rail holders (such as Bussmann CHCC series or BCM series holders).
Transformer Sizing Rules: When protecting primary circuits of control transformers, select the fuse ampacity according to NEC® Article 450 guidelines to balance full overload protection with magnetizing inrush tolerance.
To review official Class CC branch-circuit fuse standards and low-voltage current-limiting guidelines, consult the National Electrical Manufacturers Association (NEMA) Directory.
To check regional warehouse inventory availability or request commercial quotes for volume electrical fuses, visit the Control Qatar Contact Page.
