Overview
The Bussmann FNM-5 Fusetron is a time-delay supplemental fuse rated 5A at 250VAC, designed for circuits with high inrush currents and inductive loads. This Class CC midget fuse features a dual-element design that distinguishes between temporary surges and genuine overcurrent faults, providing superior protection without nuisance trips in motor control transformers, control circuit wiring, and small motor applications across industrial, commercial, agricultural, HVAC, and building automation systems.
Key Features
- Time-Delay (Dual-Element): Withstands temporary inrush without premature blowing, ideal for transformer and motor loads
- Color-Coded Green: Instantly identifies 250VAC voltage rating across electrical installations
- Melamine Tube Construction: Robust cylindrical body with nickel-plated brass end caps for secure ferrule terminal connections
- Class CC Supplemental: Provides point-of-load protection for inductive circuits up to 250VAC; not for main branch circuit protection
- Box of 10: Convenient quantity for stocking replacement fuses in control panels and equipment
Technical Specifications
- Part Number: FNM-5
- Amperage Rating: 5A
- Voltage Rating: 250VAC
- Interrupt Rating 250V AC: 200A
- Interrupt Rating 125V AC: 10,000A
- Fuse Classification: Class CC, Supplemental, Time-Delay (Dual Element)
- Body Type: Cylindrical (Cartridge)
- Dimensions (Imperial): 13/32″ × 1-1/2″
- Dimensions (Metric): 10.3mm × 38.1mm
- Terminal Type: Ferrule End
- Color Code: Green (250VAC)
- Quantity Per Box: 10 Fuses
- Certifications: UL Listed, CSA Certified
- Material: Melamine tube with nickel-plated brass end caps
Typical Applications
The Bussmann FNM-5 is engineered for supplemental protection in:
- Motor control transformer windings and circuits
- Control circuit wiring in industrial machinery and equipment
- Small motor protection in HVAC systems, agricultural equipment, and commercial installations
- Heating, ventilating, and air conditioning (HVAC) equipment circuits
- Meter circuits and general purpose circuit protection requiring time-delay characteristics
- Sensitive electronic and control equipment requiring precise overcurrent protection
Compatibility & Replacements
Compatible With
- Standard midget fuse holders and blocks rated for 13/32″ × 1-1/2″ cartridge fuses
- Bussmann modular fuse blocks (BMM series)
- DIN-Rail mounted fuse holders and switches
- Any Class CC or supplemental fuse socket accepting ferrule-end midget cartridges
- Equipment designed for 250VAC fusing with 5A protection requirement
Replaces / Drop-In Replacement For
- Original Bussmann FNM-5 fuses
- Cooper Bussmann FNM-5
- Other 5A, 250VAC time-delay supplemental midget fuses meeting UL 248-14 Class CC standards
Works With
- UL 248-14 compliant fuse standards and Class CC protection specifications
- Industrial control systems and motor protection circuits
- Electrical installations rated for 250VAC/125VAC supplemental fusing
- Equipment requiring dual-element time-delay protection characteristics
