Mersen LJD Back-Up R-Rated Medium Voltage Fuse, Ferrule Mount, 5080V

Mersen LJD Back-Up R-Rated Medium Voltage Fuse, Ferrule Mount, 5080V

The Mersen LJD Back-Up R-Rated Medium Voltage Fuse is a current-limiting, high interrupting rating fuse engineered for the short-circuit protection of medium voltage motors and motor controllers. Rated at 5080V AC (UL) with a 50 kA AC maximum interrupting rating (I1), this R-Rated back-up fuse is designed to be coordinated with overload relays in combination motor starters, with exact fuse sizing typically specified by the motor starter manufacturer. It is available with 3-inch (size D) or 4-inch (size E) diameter barrels fitted with ferrule terminals, mounted in spring-reinforced clips for a secure connection.

Key Features

• Ferrule Connection: Silver-plated copper ferrule terminals seat in spring-reinforced clips for a secure, low-resistance connection.
• High Interrupting Rating: 50 kA AC maximum interrupting rating (I1) delivers robust short-circuit protection for demanding medium voltage circuits.
• R-Rated Back-Up Protection: Speed/characteristic is R-Rated (Design Details: 6R), intended as a back-up fuse coordinated with overload relays in combination motor starters.
• Medium Voltage Rating: Rated voltage of 5080V AC (UL), suited for medium voltage motor and motor controller circuits.
• Dual Frequency Operation: Rated for 50/60 Hz AC applications.
• Visual Indication: Built-in visual indicator system provides at-a-glance blown-fuse status.
• Durable Body: Epoxy body/insulating material provides mechanical strength and dielectric protection.
• Flexible Barrel Sizing: Offered in 3-inch (size D) or 4-inch (size E) diameter barrels to match application requirements.

Technical Specifications

• Indication System: Yes
• AC or DC: AC
• Design Details: 6R
• Connection/Terminal Type: Ferrule
• Connection/Terminal Material: Silver-Plated Copper
• Mounting: Clip
• AC Max I.R./Breaking Capacity (I1): 50 kA
• Frequency: 50/60 Hz
• Rated Voltage AC (UL): 5080 V
• Body/Insulating Material: Epoxy
• Packaging: 1 EA

Typical Applications

• Medium Voltage Motor Short-Circuit Protection
• Combination Motor Starters Coordinated with Overload Relays
• Industrial Motor Control Centers
• Medium Voltage Switchgear and Motor Control Equipment

Why Mersen?

Mersen builds the LJD Back-Up R-Rated Fuse with silver-plated copper ferrule terminals, spring-reinforced clip mounting, and a durable epoxy body, backed by a 50 kA interrupting rating and integrated visual indication. That combination gives electrical professionals a dependable, code-coordinated component for short-circuit protection in demanding medium voltage motor and motor controller applications.