Bussmann JJN Series Class T Current-Limiting Fuse, Very Fast-Acting

Bussmann JJN Series Class T Current-Limiting Fuse, Very Fast-Acting

The Eaton Bussmann JJN series is a current-limiting, very fast-acting Class T fuse engineered for demanding branch-circuit protection where space and speed both matter. This family is available in ratings from 20A to 60A, covering the JJN line's standard bolt-on, non-indicating configuration. It is a common choice for large apartment complexes, multi-family meter stacks, and VFD (variable frequency drive) line protection, where compact Class T dimensions and fast clearing times help protect sensitive equipment and downstream conductors.

Key Features

• Amp Rating Range: Available in 20A, 25A, 30A, 35A, 40A, 45A, 50A, and 60A ratings to match the branch-circuit load.
• Class T Design: Compact Class T body dimensions allow use in tight panelboard and meter-stack enclosures where space is limited.
• Current-Limiting Performance: Very fast-acting operation restricts let-through energy during a fault, helping protect connected equipment and wiring.
• Bolt Connection: Standard bolt-type mounting for secure, low-resistance connections in fuse blocks and holders.
• Non-Indicating: Standard non-indicating construction for straightforward, no-frills overcurrent protection.
• Application Versatility: Suited to large apartment complexes, multi-family meter stacks, and VFD line protection where fast-acting current limitation is required.

Technical Specifications

• Compliances: Not Applicable
• Fuse Class: Class T
• Speed: Current-limiting, very fast-acting
• Connection Type: Bolt
• Indication: Non-indicating
• Style: Standard
• Amp Rating Options: 20A, 25A, 30A, 35A, 40A, 45A, 50A, 60A

Typical Applications

• Large Apartment Complexes
• Multi-Family Meter Stacks
• VFD (Variable Frequency Drive) Line Protection
• Panelboard and Meter-Bank Branch-Circuit Protection
• Commercial and Multi-Family Electrical Distribution

Why Bussmann?

Eaton Bussmann is a long-standing name in circuit protection, and the JJN Class T series delivers the current-limiting, very fast-acting performance that meter-stack and VFD applications depend on. With bolt-type connections and a compact Class T footprint spanning 20A to 60A, this series gives electrical professionals a dependable option for space-constrained, high-density installations.