MERSEN FUSE 600V 100A CLASS J TD FUSE AJT100

MERSEN FUSE 600V 100A CLASS J TD FUSE AJT100

The AJT100 delivers superior circuit protection for demanding industrial applications, with a 600VAC/400VDC voltage rating and a 100A rating for reliable performance under heavy loads. Its time-delay feature ensures dependable motor and transformer protection by withstanding high inrush currents without nuisance tripping.

SKU: AJT100MPN: AJT100
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List Price £99.91 ex VAT
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Why Choose the Mersen AJT100 Amp-Trap 2000® Fuse?

The Mersen AJT100 is a high-performance Class J time-delay current-limiting fuse developed to protect industrial and commercial electrical systems against overloads and short circuits. Part of the trusted Mersen Amp-Trap 2000® AJT series, it combines strong current-limiting performance with the ability to withstand normal motor-starting currents and transformer inrush without unnecessary fuse operation.

Rated at 100 A, the AJT100 is suitable for mains, feeders, branch circuits, motor circuits, transformers and general industrial loads. Its time-delay characteristic improves system continuity during temporary inrush conditions, while its rapid response to genuine faults helps limit peak current and damaging let-through energy.

The Mersen AJT100 is rated for operation at up to 600 V AC and 400 V DC. Its compact Class J dimensions require less panel space than many comparable Class RK fuse arrangements, while the rejection-style construction helps prevent replacement with an unsuitable fuse class.

Key Advantages

  • Class J time-delay fuse for industrial circuit protection.
  • 100 A current rating for feeders, motors and distribution equipment.
  • 600 V AC and 400 V DC voltage ratings.
  • Handles normal motor-starting and transformer-inrush currents.
  • Current-limiting performance reduces peak fault current and let-through energy.
  • 200 kA AC and 100 kA DC interrupting ratings.
  • Compact footprint helps reduce fuse-block and panel-space requirements.
  • SmartSpot® visual indicator helps identify an open fuse.

Key Features

  • Mersen Amp-Trap 2000® AJT series.
  • 100 A rated current.
  • 600 V AC rating.
  • 400 V DC rating.
  • Time-delay current-limiting operation.
  • SmartSpot® visual open-fuse indication.
  • Blade-terminal construction.
  • Fibreglass body for dimensional stability in harsh environments.
  • High-grade silica filler supports rapid arc quenching.
  • Compatible with correctly rated Class J fuse holders.

Dependable Time-Delay Protection for Industrial Equipment

The Mersen AJT100 is engineered for circuits that experience temporary inrush currents during normal operation. Its time-delay characteristic allows motors, transformers and other inductive equipment to start without nuisance fuse opening, while maintaining effective overload and short-circuit protection.

During a high-current fault, the AJT100 operates as a current-limiting device, interrupting the circuit before the prospective fault current reaches its maximum value. This reduces thermal and mechanical stress on conductors, switches, contactors, busbars and connected equipment.

When correctly selected and coordinated, Amp-Trap 2000® AJT fuses can support IEC Type 2 no-damage protection for motor-starter assemblies. The AJT100 also offers easy 2-to-1 selectivity, helping isolate the affected circuit and reduce unnecessary shutdowns elsewhere in the electrical system.

Typical Applications

  • Motor circuits and motor-control centres.
  • Main incoming circuit protection.
  • Industrial feeder circuits.
  • Branch-circuit protection.
  • Transformer primary and secondary protection.
  • Industrial control panels.
  • Panelboards and switchboards.
  • Bus duct systems.
  • Load centres.
  • Lighting, heating and general industrial loads.
  • Circuit-breaker back-up protection.

Technical Specifications

Current 100 A
Voltage 600 V
Item number AJT100
Description Fuse AJT - Class J - Time-delay 600VAC 400VDC 100A Blade SmartSpot® Amp-Trap 2000®
EAN/UPC Code 782001962487
Rated voltage AC UL 600 V
Rated voltage DC UL 400 V
Frequency (Hz) 50/60 Hz
Ampere Rating 100 A
AC or DC AC/DC
Fuse Class Class J
Speed/Characteristic Time Delay
Mounting Clip or Bolted
AC Max I.R./Breaking Capacity I1: 200 kA
Indication System Yes
Indication System Type SmartSpot®
Connection/Terminal Material Tin-Plated Copper
Connection/Terminal Type Blade
Product Diameter 27 mm
Product Length 117.6 mm
Sell Pack Quantity 5 EA
Sell Pack Weight 0.5761 kg
Sell Pack Width 136.7 mm
Sell Pack Length 152.4 mm
Sell Pack Height 26.9 mm
Product group Low Voltage UL/CSA Fuses
Body/Insulating Material GMG
Product Weight 0.1093 kg
HS Code 85361090
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Time delay

Frequently Asked Questions

What is the Mersen AJT100 used for?

The Mersen AJT100 provides time-delay overload and short-circuit protection for motors, transformers, feeders, branch circuits, control panels and industrial power-distribution equipment.

What is the current rating of the AJT100?

The Mersen AJT100 has a rated current of 100 A.

What voltage is the Mersen AJT100 rated for?

The AJT100 is rated for operation at up to 600 V AC and 400 V DC. It also carries a self-certified 700 V AC rating.

Is the AJT100 a time-delay fuse?

Yes. The AJT100 is a Class J time-delay current-limiting fuse designed to tolerate normal motor-starting and transformer-inrush currents while responding effectively to genuine overloads and short circuits.

Does the AJT100 have a blown-fuse indicator?

Yes. The standard AJT100 incorporates Mersen SmartSpot® visual indication to help identify when the fuse has opened.

What fuse holder is suitable for the AJT100?

The AJT100 should be installed in a compatible Class J fuse holder rated for at least 100 A and the applicable system voltage. Recommended Mersen fuse blocks include the FB60J100B1 single-pole and FB60J100B3 three-pole models.

Trusted Industrial Circuit Protection

Mersen Amp-Trap 2000® Class J fuses are widely specified by electrical engineers, panel builders, OEMs and maintenance professionals for dependable time-delay protection, exceptional current limitation and reliable performance in demanding industrial systems.

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