Overview
The Bussmann FRS-R-80 Fusetron is a Class RK5 dual-element, time-delay, current-limiting fuse designed for industrial motor control and power distribution circuits. Rated at 80 amperes with a voltage range of 600VAC / 300VDC, this renewable fuse delivers both motor overload protection and short-circuit protection with a 200 kA interrupting rating at 600VAC (20 kA at 300VDC). The time-delay element allows the fuse to tolerate temporary motor inrush currents while maintaining fast fault protection.
Key Features
- Dual-element, time-delay design with 10-second minimum response at 500% rated current
- Current-limiting technology reduces stress on downstream equipment during short circuits
- Non-indicating (non-renewable) body with knife blade terminals for standard R-type clips
- Approved to UL 248-12, CSA, and CE standards for global industrial use
- Cartridge construction with fiberglass-reinforced body for durability and consistent performance
- Drop-in replacement for original equipment and retrofit installations
Technical Specifications
- Amperage Rating: 80 Amperes
- Voltage Rating: 600VAC / 300VDC
- Fuse Class: RK5
- Type: Dual-Element, Time-Delay, Current-Limiting
- Interrupting Rating: 200 kA (600VAC symmetrical), 20 kA (300VDC)
- Time-Delay Response: 10 seconds minimum at 500% rated current
- Terminal Style: Knife Blade (standard R-type rejection clips)
- Body Construction: Fiberglass-reinforced cartridge
- Dimensions: 1.11 in. diameter × 7.88 in. length (28.19mm × 200.15mm)
- Weight: ~10.88 oz
- Approvals: UL 248-12, CSA, CE
Typical Applications
- Three-phase motor circuits with temporary inrush currents
- Industrial machinery and equipment with inductive loads (transformers, motor starters)
- Power distribution panels and feeder circuits rated 80A
- Control circuits requiring coordination with overload relays
- Retrofit and replacement applications where Class RK5 fuses are specified
Compatibility & Replacements
Compatible With
- Standard R-type fuse holders and clips rated for Class RK5 600V fuses
- Motor starter units and panel-mounted disconnects with R-class fuse cavities
- Electrical systems operating at 600VAC or 300VDC with 80A branch circuit protection
- Industrial control systems requiring time-delay overload protection
Replaces / Drop-In Replacement For
- Older Bussmann FRS-R-80 fuses (standard interchangeability within series)
- Similar Littelfuse FLS-R 80A Class RK5 time-delay fuses (verify holder compatibility)
- Other manufacturer 80A RK5 time-delay fuses per UL 248-12 Class RK5 specifications
Works With
- Class RK5 rejection fuse clips and holders
- Motor control centers and industrial control panels
- Coordinated with thermal-magnetic overload relays for complete branch circuit protection
- Standard electrical safety systems relying on UL 248-12 Class RK5 performance
