FNQR-12 TIME DELAY FUSE BUSSMANN
FNQR-12 TIME DELAY FUSE BUSSMANN – Industrial 12A 600VAC Class CC Time-Delay Current-Limiting Fuse
The FNQR-12 TIME DELAY FUSE BUSSMANN (Model FNQ-R-12) is an premium-performance, current-limiting Class CC time-delay power fuse manufactured by Eaton’s Bussmann series. Engineered specifically to provide superior protection for control transformers, motor branch circuits, lighting panelboards, and automated control cabinets, this 12-amp, 600 VAC LIMITRON™ fuse combines exceptional surge tolerance with high-speed short-circuit interruption.
Designed with advanced time-delay characteristics, the FNQR-12 TIME DELAY FUSE BUSSMANN features a minimum 12-second time-delay at 200%Â of its rated current. This delayed action permits temporary, harmless magnetizing inrush surges from control transformers and startup currents from small AC motors to pass safely without premature opening. In the event of a severe fault, however, its current-limiting operation interrupts high-energy short circuits up to 200 kA RMSÂ Symmetrical at 600 VAC. Equipped with a physical Class CC rejection tip, it actively prevents lower-rated supplementary or non-rejection fuses from being inserted into protected circuits.
Key Features of the FNQR-12 TIME DELAY FUSE BUSSMANN
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Class CC Rejection Feature: Built with a standardized Class CC rejection tip that physically keys into Class CC fuse blocks, preventing accidental insertion of non-current-limiting or lower-voltage fuses.
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12-Second Time-Delay Capability: Delivers a minimum 12-second time-delay at 200% rated load, effectively eliminating nuisance fuse blowouts caused by transformer inrush or motor starting currents.
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High 200 kA Breaking Capacity: Rated to interrupt fault currents up to 200 kA RMS Symmetrical at 600 VAC, ensuring full NEC® Section 110.9 safety compliance in high available fault current panels.
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Advanced Current Limitation: Drastically restricts thermal (I^2t) and magnetic peak let-through energy under short-circuit conditions, shielding downstream relays, switches, and contactors.
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Compact Physical Footprint: Standardized 13/32” x 1-1/2” midget size allows high-density mounting in space-restricted industrial control enclosures.
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High-Strength Melamine Casing: Constructed with a durable melamine body that maintains structural integrity and arc-quenching capability under extreme thermal and electrical stress.
Common Applications and Practical Usage
The high breaking capacity and specialized surge handling of the FNQR-12 TIME DELAY FUSE BUSSMANN make it a preferred choice across industrial machinery and commercial automation:
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Control Transformer Primary Protection: Provides maximum protection for industrial control transformer primaries subject to intense magnetizing inrush surges.
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Small Motor Branch Circuits: Protects fractional horsepower AC motors, small pumps, blowers, and motor controllers against overloads and short circuits.
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Solenoid & Contactor Coils: Prevents coil destruction in industrial solenoids, electromagnetic valves, and heavy-duty relay circuits.
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Industrial Automation & Panelboards: Ideal for protecting auxiliary circuits, power supplies, and pilot equipment in compact 600 VÂ machine control cabinets.
Technical Specifications
The core electrical, physical, and compliance parameters for the FNQR-12 TIME DELAY FUSE BUSSMANN are detailed below:
| Parameter Specification | Technical Details & Operational Values |
| Component Classification | Industrial Class CC Time-Delay Current-Limiting Fuse |
| Primary Target Keyword | FNQR-12 TIME DELAY FUSE BUSSMANN |
| Brand / Series | Eaton Bussmann Series / LIMITRONâ„¢ FNQ-R |
| Catalog Model / Part No. | FNQ-R-12 (FNQR-12) |
| Amperage Rating | 12 Amps (12 A) |
| Voltage Rating | 600 VAC |
| Interrupt Rating (IR) | 200 kA RMSÂ Symmetrical at 600 VAC |
| 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 mm x 38.1 mm) |
| Body Material & Caps | High-Grade Melamine Casing with Plated End Caps & Rejection Tip |
| Agency Certifications | UL Listed (Std 248-4, Guide JDDZ), CSA Certified, CE, RoHS Compliant |
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: Follow NEC® Article 450 sizing guidelines when selecting primary fuses for control transformers to balance inrush withstand capability with short-circuit protection.
To review official Class CC current-limiting fuse specifications and industrial control protection standards, 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.







