Bussmann Time Delay Fuse FRN-R Series 40A 250VAC/125VDC Class RK5 Dual Element Ferrule End

Bussmann Time Delay Fuse FRN-R Series 40A 250VAC/125VDC Class RK5 Dual Element Ferrule End

Professional-Grade Motor and Circuit Protection with Current Limiting Technology

The Bussmann Time Delay Fuse FRN-R Series 40A delivers superior electrical protection and circuit safety for motor circuits and time-delay applications. This Class RK5 time delay fuse features dual element current limiting technology designed for electrical contractors, industrial facilities, and commercial installations, providing the reliable overcurrent protection and industry-leading safety that electrical professionals demand.

Professional Features & Benefits

Advanced Time Delay Protection

• Dual Element Design - Provides superior time delay characteristics with 10 second response at 500% rated current for motor starting protection
• 40 Ampere Rating - Handles continuous current up to 40A with reliable overcurrent protection for medium-duty applications
• Current Limiting Technology - Reduces peak let-through current and energy to protect downstream equipment from fault damage
• Class RK5 Performance - Delivers excellent selectivity and coordination with upstream protective devices

Safety & Standards Compliance

• High Interrupt Rating - 200 kAIC at 250VAC and 20 kAIC at 125VDC for reliable fault clearing capability
• CE Marked Compliance - Meets international safety standards for global electrical installations
• Non-Indicating Design - Professional-grade construction without visual indication for standard panel applications

Technical Specifications

40 ampere rating, 250VAC/125VDC voltage rating, 200 kAIC interrupt rating at 250VAC, 20 kAIC at 125VDC, Class RK5 current limiting, ferrule end connections, dual element time delay design, 10 second response time at 500% rated current, 3.0 x 0.81 x 0.81 inches dimensions, 0.11 lb weight, standard packaging.

Installation & Setup

1. Verify power is OFF and use proper lockout/tagout procedures before installation
2. Confirm fuse holder is rated for Class RK5 fuses and 40A continuous current
3. Insert ferrule ends fully into fuse clips ensuring secure mechanical connection
4. Verify proper fuse orientation and that connections are tight and secure
5. Test installation with appropriate electrical testing equipment before energizing
6. Document installation per NEC requirements and facility maintenance procedures

Professional Applications

Ideal for:

• Motor Protection Circuits - HVAC motors, pump motors, conveyor systems, and industrial machinery requiring time delay protection
• Transformer Secondary Protection - Distribution transformers, control transformers, and power supply protection
• Control Panel Applications - Motor control centers, electrical panels, and industrial control systems
• Lighting Circuit Protection - Commercial lighting panels, ballast protection, and LED driver circuits
• Industrial Machinery - Manufacturing equipment, process control systems, and automated machinery
• Commercial Buildings - Office buildings, retail facilities, and institutional electrical systems
• Power Distribution - Electrical distribution panels, switchgear, and load centers
• HVAC Systems - Air handling units, chillers, and building automation systems

Dual Element Time Delay Advantage

Bussmann dual element technology provides superior motor starting protection by allowing temporary overloads while quickly clearing dangerous fault currents. The time delay element handles motor inrush currents and temporary overloads, while the current limiting element provides fast fault clearing and arc suppression for maximum electrical safety and equipment protection.

Why Choose Bussmann Quality?

Bussmann commitment to electrical safety includes rigorous testing, international compliance standards, and reliable overcurrent protection technology. Each FRN-R series fuse delivers consistent performance, selective coordination capability, and the current limiting protection that electrical professionals trust for critical motor and circuit protection applications.