Overview
The Bussmann FNM-1-4/10 is a time-delay (slow-blow) dual-element supplemental fuse designed for AC electrical circuits requiring inrush current protection. Rated at 1.4 amperes and 250 volts, this fuse is ideal for protecting transformer primaries, motor circuits, and other inductive loads commonly found in industrial control panels and equipment. The FNM-1-4/10 features a melamine tube construction with nickel-plated endcaps and conforms to UL Standard 248-14, providing reliable circuit protection in residential, commercial, and industrial settings.
Key Features
- Time-delay (slow-blow) design handles high inrush currents without nuisance trips
- Dual-element construction for precise load protection
- Melamine tube body with nickel-plated bronze endcaps for durability
- Class 5AG midget fuse format (13/32″ diameter × 1-1/2″ length)
- UL Listed, CSA Certified, and RoHS compliant
- Compact size suitable for space-constrained panel applications
Technical Specifications
- Current Rating: 1.4 amp (1-4/10 amp)
- Voltage Rating: 250 VAC
- Interrupt Rating: 35 A at 250 VAC; 10 kA at 125 VAC
- Fuse Class: 5AG (supplemental midget)
- Speed: Time-Delay (T) / Slow-Blow
- Ferrule End Configuration: Ferrule × Ferrule
- Dimensions: 13/32″ (10.3 mm) diameter × 1.5″ (38.1 mm) length
- Construction Material: Melamine tube with nickel-plated endcaps
- Certifications: UL Listed (File E19180), CSA Certified (File 53787)
Typical Applications
- Motor starter circuits with high inrush current requirements
- Transformer primary circuit protection
- Relay and ballast protection in control systems
- Small motor and inductive load circuits up to 250 VAC
- Supplemental protection for low-power automation and HVAC equipment
Compatibility & Replacements
Compatible With
- Bussmann FNM series fuse blocks (BMM modular blocks)
- HPM and HPD panel-mount fuse holders rated for 13/32″ × 1-1/2″ cartridge fuses
- DIN-rail mounted fuse holders with midget fuse receptacles
- Any 250 VAC electrical circuit requiring Class 5AG supplemental protection
- Industrial control panels, transformer protection circuits, and motor controls
Replaces / Drop-In Replacement For
- Bussmann FNM-1-4/10 (all revisions)
- Fusetron FNM-1-4/10
- Cooper Bussmann FNM-1-4/10
- Generic 1.4 A time-delay midget fuses rated 250V, Class 5AG
Works With
- Any fuse holder designed for 5AG midget cartridge fuses (ferrule end configuration)
- Circuit protection schemes requiring time-delay fuse selectivity
- Control systems using legacy 250 VAC supplemental protection standards
- Industrial equipment rated for Class 5AG supplemental fuses per UL 248
