Overview
The S&C Electric 124200 is a 65E-rated SM-4 power fuse refill unit engineered for outdoor distribution substations and high-voltage industrial systems rated at 34.5 kV. SM-4 Power Fuses are rated 200 amperes continuous and utilize SM-4 Refill Units offered in a variety of ampere ratings, in three different speeds — S&C Standard, Slow, and Coordinating. This refill unit is designed to provide fast, positive fault interruption while maintaining precise time-current characteristics for system coordination.
Key Features
- Precision-engineered nondamageable silver or nickel-chrome fusible elements with time-current characteristics that are precise and permanently accurate
- Provides interrupting ratings of up to 15,600 amperes symmetrical
- Source-side devices may be set for faster operation than practical with other power fuses or circuit breakers, thereby providing better system protection without compromising coordination
- Designed for quick, positive arc elongation and efficient deionizing action
- Rated for continuous operation at 200 amperes in SM-4 holders
Technical Specifications
- Voltage Rating: 34.5 kV nominal
- Ampere Rating: 65E (Standard Speed)
- Continuous Current Capacity: 200 amperes
- Interrupting Rating: Up to 15,600 amperes symmetrical
- Fusible Element: Silver or nickel-chrome
- Compatible Holder: SM-4 Power Fuse holder
- Speed Class: S&C Standard
- Certification: ISO 9001:2000
Typical Applications
- Outdoor distribution substation transformer protection
- Medium-to-large power transformer protection on utility systems
- Cable and feeder protection in commercial and industrial installations
- Capacitor bank protection in power distribution systems
- System coordination in multi-level protection schemes
Compatibility & Replacements
Compatible With
- SM-4 Power Fuse holders for outdoor distribution
- Systems and equipment rated 34.5 kV and below
- Utility, commercial, and industrial power distribution networks
- Standard medium-voltage switchgear and substations
Replaces / Drop-In Replacement For
- Original equipment manufacturer (OEM) SM-4 65E refill units
- Direct replacement for standard 65E S&C Power Fuse elements in SM-4 applications
Works With
- S&C Electric SM-4 outdoor distribution power fuse holders
- Standard 34.5 kV medium-voltage distribution equipment and protection schemes
- Time-current coordination studies and selective protection practices
