Mersen AJT100 Time Delay Class J Blade Fuse 100A 600V

Product Description

The MERSEN AJT100 is a 100-amp, 600-volt AC Class J time delay blade fuse designed for motor starting circuits, transformer protection, and general industrial power distribution. Part of the Amp-Trap 2000 AJT series, it delivers a 300kA interrupting rating and extreme current-limiting performance to keep peak let-thru current low. The fiberglass body provides dimensional stability in harsh industrial environments, while high-grade silica filler ensures fast arc quenching. A solid-state SmartSpot indicator signals a blown fuse without requiring a meter, helping technicians diagnose faults quickly. Licensed electricians and industrial maintenance professionals are the primary installers.

The AJT100 is suited for industrial, commercial, and automotive electrical systems where motor starting inrush and transformer inrush currents demand time delay protection. Its unique Class J dimensions prevent substitution with lower-rated fuse classes, reducing installation errors in panel and distribution board applications. The compact footprint requires less mounting space than many competing designs and is compatible with smaller, more economical fuse blocks, making it practical for both new installations and retrofit work in commercial and industrial facilities.

Key Features

• 100A ampere rating at 600V AC with 300kA interrupting rating
• Time delay design accommodates motor starting and transformer inrush currents
• Solid-state SmartSpot indicator provides visual blown-fuse identification
• Class J dimensions prevent replacement with incorrect fuse classes
• Fiberglass body with high-grade silica filler for fast arc quenching and dimensional stability
• Metal-embossed date and catalog number for traceability in industrial settings
• Easy 2-to-1 selectivity ratio supports nuisance shutdown prevention

Compatibility

Designed for use in Class J fuse holders and fuse blocks rated for 100A and 600V AC in industrial, commercial, and automotive electrical distribution applications.

Installation Notes

Installation and replacement must be performed by a qualified electrician in accordance with the National Electrical Code (NEC) and applicable local codes. Always de-energize and lock out the circuit before removing or installing fuses. Verify that the fuse holder and fuse block are rated for Class J fuses at 100A and 600V AC before installation. Never substitute a fuse of a different class or ampere rating in a Class J-specific holder.