Overview
The Bussmann Fusetron FRN-R-4 is a Class RK5 dual element, time-delay fuse designed for dependable branch circuit and equipment protection in industrial and commercial electrical systems. This 4-ampere, 250 Vac/125 Vdc fuse provides current-limiting action with an interrupting rating of 200 kA at 250 Vac and 20 kA at 125 Vdc, making it ideal for motor circuits, distribution panels, and machinery control applications where nuisance trips must be minimized.
Key Features
- Dual-element, time-delay construction with 8-second response at 500% overload
- Current-limiting technology reduces peak fault current and thermal stress
- Non-indicating ferrule-end cartridge design for standard clip-on fuse holders
- UL 248-12 certified, CSA C22.2, and CE compliant
- Available in lot of 9 units, new in box condition
Technical Specifications
Comprehensive specifications for the Bussmann FRN-R-4 fuse:
- Amperage Rating: 4 A
- Voltage Rating: 250 Vac / 125 Vdc
- Fuse Class: RK5
- Type: Dual Element, Time Delay
- Interrupting Rating (AC): 200 kA @ 250 Vac
- Interrupting Rating (DC): 20 kA @ 125 Vdc
- Terminal Style: Ferrule end x ferrule end
- Speed Rating: 8 seconds @ 500% overload
- Indication: Non-indicating
- Certifications: UL 248-12, CSA C22.2 No. 32, CE
- Series Name: Fusetron FRN-R
Typical Applications
The Bussmann Fusetron FRN-R-4 is widely used in:
- Industrial motor control circuits and starters
- Main and branch circuit protection in distribution panels
- Equipment and machinery protection in manufacturing facilities
- Power distribution systems requiring Class RK5 performance
- Control transformers and low-voltage power supplies
Compatibility & Replacements
Compatible With
- Standard clip-on cartridge fuse holders accepting ferrule-end cartridges
- Industrial control panels rated for 250 Vac or 125 Vdc circuits
- Equipment and machinery requiring Class RK5 fuse protection
- UL-listed and CE-marked electrical systems
Replaces / Drop-In Replacement For
- Earlier generation Bussmann Fusetron FRN-R-4 cartridges
- Cooper Bussmann FRN-R-4 equivalents
- Other 4A Class RK5 dual element fuses meeting UL 248-12 specifications
Works With
- Standard cartridge fuse holders for 0.56-inch diameter, 2-inch length cartridges
- Power distribution systems and motor control centers (MCCs)
- Industrial control systems requiring RK5 current-limiting fuse protection
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