Overview
Mersen A480R3R-1HE is a back-up R-rated, current-limiting medium-voltage fuse designed specifically for short-circuit protection of 4.8 kV motors and motor controllers. The Amp-Trap® ferrule-mount design delivers high interrupting capacity and superior coordination with overload relays in combination motor starters. This fuse is UL-recognized and suitable for industrial and commercial motor-protection applications requiring precise electrical protection and fast response.
Key Features
- Back-up R-rated current-limiting fuse with 65 kA interrupt rating
- Ferrule terminal mounting for standard clips and interchangeability across brands
- Size D barrel (3 inches) with 3R class rating and hookeye visual indicator
- Metal-embossed catalog number and manufacturing date for traceability
- UL-recognized Amp-Trap® design with blown-fuse indicator for positive identification
- Silver-plated copper contacts and 2 lb tripped force for reliable operation
Technical Specifications
- Voltage Rating: 4800 VAC
- Current Rating: 100 A
- Class: R-Rated (3R size designation)
- Series: Amp-Trap® A480R
- Barrel Diameter: 3 inches (Size D)
- Length: 16.13 inches
- Mounting Style: Ferrule, clip-mounted
- Interrupt Rating: 65 kA
- Terminal Type: Ferrule with silver-plated copper
- Tripped Force: 2 lb @ 0.50 inches
- Certifications: UL-Recognized
- Catalog Number: S203428 / A480R3R-1HE
Typical Applications
The A480R3R-1HE is commonly used in:
- Medium-voltage motor circuit protection (4.8 kV systems)
- Combination motor starters and soft-start controllers
- Oil and gas drilling equipment
- Mining and mineral processing installations
- Water and wastewater treatment plants
- Industrial compressor and pump protection
- Utility substation switchgear (back-up protection)
Compatibility & Replacements
Compatible With
- Medium-voltage motor starters rated 4.8 kV
- Combination motor controllers with R-rated fuse provisions
- Standard ferrule-mount fuse clips (12.5-inch clip centers)
- Soft starters and variable frequency drives requiring back-up protection
- Motor branch-circuit short-circuit protection applications per NFPA 70
Replaces / Drop-In Replacement For
- Mersen A480R3R-1 (standard version without hookeye)
- Other Amp-Trap® A480R 3R fuses with ferrule mount at 100A
- Legacy Ferraz Shawmut R-rated 4.8 kV 100A fuses (model cross-compatibility confirmed by distributor technical data)
Works With
- Ferrule-mounted clip systems across major manufacturers
- Medium-voltage protection schemes coordinated with overload relays
- ANSI/IEEE Standard C37.41 (medium-voltage fuse standards)
- UL Standard 248-4 (high-voltage fuses)
- IEC 60282 high-voltage fuse standards (international applications)
