Overview
The Ferraz Shawmut AJT80 is a Class J time delay fuse engineered for superior circuit protection in industrial and commercial electrical systems. Manufactured by Mersen under the Amp-Trap 2000 line, this 80-ampere, 600VAC/500VDC fuse delivers IEC Type 2 “no damage” protection to main, feeder, and branch circuits. The AJT80 is housed in a compact blade cartridge design that requires approximately half the space of traditional Class RK fuses, making it ideal for dense panel configurations.
Key Features
- Time Delay Characteristic: Handles harmless motor and transformer inrush currents without nuisance trips
- Superior Current Limiting: Most current-limiting UL Class J fuse available; minimizes thermal and mechanical stress on connected equipment
- SmartSpot Visual Indicator: Optional open fuse indicator for at-a-glance confirmation of fuse status
- Compact Blade Mount Design: Dual blade terminals fit standard Class J fuse blocks and clips
- Wide Rating Range: AJT series spans 1–600A, supporting diverse load requirements
- UL/CSA Listed: Meets North American safety standards (UL 248, CSA C22.2 No. 198)
Technical Specifications
The AJT80 delivers reliable, current-limiting protection across a range of electrical infrastructure:
- Continuous Current Rating: 80A
- Voltage Rating: 600VAC / 500VDC
- Interrupt Rating: 200 kA @ 600VAC
- Fuse Class: J (Class J)
- Speed Characteristic: Time Delay (TD)
- Mounting Style: Blade Terminal, Clip Mount
- Cartridge Diameter: 1.06″ (26.92 mm)
- Cartridge Length: 4⅝″ (117.6 mm)
- Body Material: Fiberglass
- Weight per Unit: 4.48 oz
- Certifications: UL 248-15, CSA C22.2 No. 198
Typical Applications
- Motor control centers and pump applications (requiring soft-start tolerance)
- Transformer primary and secondary protection
- Industrial feeder and branch circuits
- HVAC systems and commercial electrical distribution panels
- Manufacturing equipment requiring inrush current accommodation
- Any Class J-rated fuse block or clip-mount configuration rated 600VAC or less
Compatibility & Replacements
Compatible With
- Class J fuse blocks and fusible disconnects (600VAC rated)
- Standard electrical distribution panels with J-rated provisions
- Eaton Cooper Bussmann LPJ and LPJ-SP fuse blocks
- Littelfuse J-series fuse holders and clip mounts
- Ferraz Shawmut / Mersen AJT-series fuse blocks
Replaces / Drop-In Replacement For
- Eaton Cooper Bussmann LPJ-80SP
- Littelfuse JTD80, JTD080
- Mersen A4J80 (older designation)
- Ferraz AJT80N (alternate designation)
Works With
- Any UL-compliant 600VAC / 500VDC Class J fuse block or clip-mount system
- Industrial control systems and panelboards using Class J protection schemes
- Motor soft-starters and variable frequency drives requiring time delay characteristics
- Building management and facility electrical distribution systems
