Overview
The Bussmann FNQ-20 is a Class CC time-delay cartridge fuse designed for supplementary circuit protection in industrial and commercial control applications. This lot includes 10 units, each rated 20A at 500VAC with 10 kAIC interrupting capacity. Bussmann FNQ-20 fuses are engineered to tolerate high inrush currents common in motor control transformers, relays, and ballast circuits while still providing reliable overcurrent protection.
Key Features
- Time-delay (slow-blow) characteristic tolerates inrush currents up to 85 times full-load rating
- Fiber tube body with nickel-plated brass ferrule endcaps for corrosion resistance
- Class CC cartridge format (13/32″ × 1-1/2″) fits standard fuse holders
- 10 kAIC interrupting rating at 500 Vac
- UL listed, CSA certified, RoHS compliant
- Non-indicating design—replacement required on fuse operation
Technical Specifications
- Fuse Type: Class CC, Midget Cartridge
- Rated Current: 20A
- Voltage Rating: 500 VAC
- Speed Characteristic: Time-Delay (Slow-Blow)
- Interrupting Rating: 10 kAIC @ 500 Vac
- Physical Size: 13/32″ Dia × 1-1/2″ L (10.3 × 38.1 mm)
- End Configuration: Ferrule × Ferrule
- Body Material: Fiber tube with nickel-plated brass endcaps
- Certifications: UL 248-4, CSA Class-CC (CSA 1422-01), RoHS
- Quantity Per Order: 10 units
Typical Applications
Bussmann FNQ-20 fuses are widely used for:
- Motor control transformer protection
- Circuits experiencing high inrush currents (control relays, solenoids)
- Small motor starters and soft-start circuits
- Electronic equipment branch circuit protection
- Ballast and lamp circuit supplementary protection
Compatibility & Replacements
Compatible With
- Any standard Class CC cartridge fuse holder (13/32″ × 1-1/2″)
- Motor control centers and branch circuit panels rated 500V or higher
- Transformer protection circuits (NEC Article 450)
- Control system circuits requiring time-delay protection
- Fuse blocks and ferrule-end fuse clips (standard .410″ contact)
Replaces / Drop-In Replacement For
- Littelfuse FLQ-20 (time-delay Class CC alternative)
- Mersen A50P20 (Class CC time-delay equivalent)
- Verify part-specific compatibility with your fuse holder before ordering
Works With
- Standard industrial fuse holders and blocks rated for Class CC cartridges
- Transformer protection circuits per NEC 450.3
- Motor control circuits per NEC Article 430
- Any 500 VAC control or branch circuit protection application










