Overview
The Bussmann FRS-R-175 Fusetron is a current-limiting, dual-element time-delay fuse engineered for industrial electrical systems, particularly motor control circuits. Built to UL Class RK5 standards, it provides coordinated protection against both overload and short-circuit conditions while permitting brief inrush currents typical of motor startup and transformer energization.
Key Features
- Dual-Element Design: Separate overload and short-circuit elements enable selective coordination and sized fusing as close as 125% of motor full-load amps (FLA)
- 10-Second Time Delay: Minimum 10-second delay at 500% rated current allows motor acceleration without nuisance trips
- Current-Limiting: 200,000 ampere symmetrical interrupting rating reduces available fault current, protecting downstream equipment
- Cartridge Body: Blade terminal design with 1.84-inch diameter and 9.63-inch length fits standard RK5 fuse holders
- Renewable Design: Permits refurbishment for cost-effective circuit protection renewal
- Safety Features: Insulated end caps reduce exposure to live parts and extend air gap distance between adjacent mounted fuses
Technical Specifications
This dual-element fuse delivers reliable performance across critical industrial applications requiring both motor protection and selective coordination.
Typical Applications
- Three-phase and single-phase motor circuits
- Control transformers and auxiliary power circuits
- Compressors, pumps, and fan motor protection
- Industrial machinery with inductive load characteristics
- Selective coordination installations requiring upstream/downstream fuse compatibility
Compatibility & Replacements
Compatible With
- Standard RK5 cartridge fuse holders (knife-blade mounting)
- 600VAC industrial distribution panels and motor control centers
- IEC and UL-compliant power distribution systems
- Motor starter circuits requiring time-delay protection
Replaces / Drop-In Replacement For
- Previous-generation Bussmann FRS-R-175 units
- Equivalent Class RK5 dual-element 175A fuses from other manufacturers
Works With
- UL Class RK5 fuse rejection holders (blade-terminal cartridges)
- Selective coordination with downstream RK5 fuses (2:1 amp ratio coordination available)
- Standard industrial AC power systems up to 600VAC
- DC circuits up to 300VDC
