FNQR-1/2 TIME DELAY FUSE BUSSMANN

FNQR-1/2 TIME DELAY FUSE BUSSMANN – Industrial 0.5A 600VAC Class CC Time-Delay Current-Limiting Fuse

The FNQR-1/2 TIME DELAY FUSE BUSSMANN (Model FNQ-R-1/2) is a high-performance, current-limiting Class CC time-delay power fuse manufactured by Eaton’s Bussmann series. Engineered specifically to provide high-level protection for control transformers, solenoids, relays, and automated control circuits, this $0.5\text{-amp}$ ( $1/2\text{A}$ ), $600\text{ VAC}$ LIMITRON™ fuse balances rapid short-circuit interruption with high tolerance for temporary current surges.

Featuring specialized time-delay characteristics, the FNQR-1/2 TIME DELAY FUSE BUSSMANN provides a minimum 12-second time-delay at $200\%$ of its rated current. This delayed response permits temporary magnetizing inrush surges from small control transformers and coil energization spikes to pass safely without premature opening. Under catastrophic fault conditions, its fast current-limiting operation interrupts high-energy short circuits up to $200\text{ kA RMS}$ Symmetrical at $600\text{ VAC}$ . Constructed in a compact $10.3 \times 38.1\text{ mm}$ ( $13/32'' \times 1-1/2''$ ) size, it features a physical Class CC rejection tip that prevents non-current-limiting or lower-rated supplementary fuses from being inserted into protected circuits.

Key Features of the FNQR-1/2 TIME DELAY FUSE BUSSMANN

Class CC Rejection Feature: Built with a standardized Class CC rejection end pin that physically keys into Class CC fuse blocks, preventing accidental over-fusing or substituting lesser-rated devices.
12-Second Time-Delay Performance: Delivers a minimum $12\text{-second}$ time-delay at $200\%$ rated load, absorbing transformer magnetizing inrush surges without nuisance tripping.
High $200\text{ kA}$ Interrupting Capacity: Rated to safely interrupt short-circuit currents up to $200\text{ kA RMS}$ Symmetrical at $600\text{ VAC}$ , fulfilling National Electrical Code (NEC®) Section 110.9 safety requirements.
Advanced Current Limitation: Drastically restricts thermal ( $I^2t$ ) and magnetic peak let-through energy during heavy short circuits, shielding delicate downstream electronics, relays, and switches.
Compact Physical Footprint: Standardized $13/32'' \times 1-1/2''$ midget size allows high-density mounting in space-restricted control enclosures and panelboards.
High-Strength Melamine Casing: Constructed with a high-grade melamine tube that provides high mechanical strength and thermal stability under fault conditions.

Common Applications and Practical Usage

The high breaking capacity, low ampacity rating ( $0.5\text{A}$ ), and specialized surge handling of the FNQR-1/2 TIME DELAY FUSE BUSSMANN make it an ideal component across control machinery and automation:

Control Transformer Primary Protection: Protects primary circuits of small industrial control transformers against short circuits while bypassing magnetizing inrush currents.
Solenoid & Valve Coil Protection: Safeguards low-current solenoid coils, electromagnetic valves, and actuators from continuous overload thermal damage.
Relay & Pilot Circuit Protection: Protects auxiliary control loops, sensing circuits, and pilot indicators in industrial machine panels.
Industrial Control Cabinets: Essential component for protecting sensitive low-current control networks in $600\text{V}$ automation machinery.

Technical Specifications

The core electrical, physical, and compliance parameters for the FNQR-1/2 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-1/2 TIME DELAY FUSE BUSSMANN
Brand / Series	Eaton Bussmann Series / LIMITRON™ FNQ-R
Catalog Model / Part No.	FNQ-R-1/2 (FNQR-1/2)
Amperage Rating	$0.5\text{ Amps}$ ( $1/2\text{A}$ / $500\text{ mA}$ )
Voltage Rating	$600\text{ VAC}$
Interrupt Rating (IR)	$200\text{ kA RMS}$ Symmetrical at $600\text{ VAC}$
Response Characteristic	Time-Delay (Min. $12\text{ seconds}$ at $200\%$ current)
Fuse Class & Form Factor	UL Class CC Rejection Ferrule ( $13/32'' \times 1-1/2''$ / $10.3\text{ mm} \times 38.1\text{ mm}$ )
Body Material & Caps	Melamine Tube 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 ensure adequate inrush tolerance while maintaining short-circuit protection.

To review official Class CC low-voltage branch-circuit standards and current-limiting fuse 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.

Electronics & Electrical Trading W.L.L

FNQR-1/2 TIME DELAY FUSE BUSSMANN