Overview
The Bussmann FRS-R-175 is a Class RK5 time-delay dual-element fuse delivering reliable protection for motor circuits, combination starters, and power distribution equipment. Built with Bussmann’s Fusetronâ„¢ dual-element design, this 175 amp fuse provides coordinated overload and short-circuit protection while tolerating temporary motor inrush currents.
Key Features
- Dual-Element Construction: Separate overload element provides best time-delay performance for sizing as close as 125% of motor Full Load Amps (FLA)
- Time-Delay Response: 10 seconds minimum time-delay at 500% of rated current
- Current-Limiting: 200 kA interrupting rating at 600 Vac and 20 kA at 300 Vdc
- Blade Terminal Connection: Blade terminal with rejection-type body design for Class RK5 rated fuse holders
- Energy Efficient: Advanced protection with dual-element, time-delay construction
Technical Specifications
- Rating: 175 amp
- Voltage: 600 VAC / 300 VDC
- Interrupt Rating: 200 kA at 600 Vac; 20 kA at 300 Vdc
- Class: Class RK5
- Series: FRS-R (Fusetron Time-Delay)
- Indicating: Non-Indicating
- Body Material: Fiberglass cartridge
- Dimensions: 1.61 in diameter × 9.63 in length
- Response Time: 10 seconds at 500% rated current
- Approvals: UL 248-12, CSA, CE
Typical Applications
- Combination Starters and Motor Control Centers
- Machinery Disconnects
- Power Panelboards
- Large industrial motors and pump circuits
- Equipment requiring coordinated overload and fault protection
Compatibility & Replacements
Compatible With
- Class RK5 fuse holders (blade terminal rejection type)
- Combination motor starters with 600V circuits
- Industrial power distribution and control panels
- Equipment rated 600 VAC / 300 VDC systems
- Motor circuits with 175A full-load current
Replaces / Drop-In Replacement For
- Littelfuse FLSR equivalents and Mersen TRS-R models in the 175A Class RK5 rating
- Other Class RK5 175A time-delay fuses in blade terminal design
Works With
- Standard Class RK5 UL 248-12 rated fuse holders
- 600 VAC industrial control systems
- Motor branch circuit protection schemes per NEC Article 430
- Panelboards and disconnect switches rated for 600V blade-terminal fuses












