Overview
The Cooper Bussmann FRS-R-40 is a Fusetron dual-element, time-delay (slow-blow) fuse designed for Class RK5 applications. Rated at 40 amperes and 600V AC (250V DC), this current-limiting fuse offers superior protection for motor circuits, transformers, and branch circuits subject to temporary inrush currents. This lot includes three units, all tested and fully functional.
Key Features
- Dual-Element Design: Provides the best time delay performance, allowing closer sizing and superior protection of motors and transformers
- Class RK5 Current-Limiting: 200 kA interrupting rating at 600 Vac and 20 kA at 250 Vdc
- Time-Delay (Slow-Blow): 10 S @ 500% Response Time, tolerating harmless inrush surges while protecting against true faults
- Ferrule Terminal: Ferrule End X Ferrule End Connection for secure panel mounting
- Renewable Design: Non-indicating fuse compatible with standard RK5 holders
- UL/CSA Certified: UL Listed Std. 248-12 Class RK5 Guide JDDZ File E4273 CSA Certified Class 1422-02 File 53787 CE
Technical Specifications
- Rated Current: 40 amperes
- Voltage Rating: 600V AC / 250V DC
- Fuse Class: RK5
- Type: Time-Delay (Slow-Blow)
- Series: FRS-R (Fusetron)
- Interrupting Rating: 200 kA @ 600 VAC; 20 kA @ 250 VDC
- Body Diameter: 1.06 inches (27 mm)
- Overall Length: 5.5 inches (140 mm)
- Terminal Type: Ferrule
- Weight: 0.31 lbs per unit
- Material: Fiberglass body
- Response Time: 10 seconds @ 500% current
Typical Applications
- AC induction motor circuits and soft-start protection
- Power distribution and branch circuits in industrial panelboards
- Transformer primary protection in motor control centers
- Machinery disconnects and combination starters
- Equipment requiring dual-element time-delay protection against overloads and short circuits
Compatibility & Replacements
Compatible With
- Standard Class RK5 fuse holders and rejection-type fuse blocks
- Power panelboards rated 600V AC
- Motor control centers (MCCs)
- Combination starters and disconnects
- Industrial machinery with 600V distribution systems
Replaces / Drop-In Replacement For
- Older FRS-R-40 units from prior manufacturing batches
- Other Class RK5 40A/600V time-delay fuses in ferrule-terminal configuration
- Verify compatibility with your control system integrator before ordering to confirm holder type and electrical requirements
Works With
- Class RK5 rejection-type fuse holders (standard 600V panelboards)
- NEMA and IEC-compliant motor protection schemes
- Soft-start drives and motor controllers requiring coordinated overload protection
- Industrial automation control systems with 600V distribution
