MERSEN FUSE 600V 450A CLASS J TD FUSE AJT450

MERSEN FUSE 600V 450A CLASS J TD FUSE AJT450

The AJT450 Amp-Trap 2000® SmartSpot® fuse offers superior circuit protection for demanding industrial applications, with a 450A rating and robust dual voltage capability (600VAC/500VDC). Its time-delay characteristic ensures reliable operation under temporary overloads, reducing unnecessary downtime and nuisance tripping.

SKU: AJT450MPN: AJT450
Price
List Price £636.24 ex VAT
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Why Choose the Mersen AJT450 Class J Time-Delay Fuse?

The Mersen AJT450 is a high-capacity Class J time-delay fuse designed to provide dependable overcurrent protection in demanding industrial electrical systems. Part of the established Mersen Amp-Trap 2000® AJT series, it combines time-delay operation with advanced current-limiting performance, making it suitable for main circuits, feeders, motor branch circuits, transformers and heavy industrial machinery.

The AJT450 is engineered to withstand normal temporary inrush currents produced during motor starting and transformer energisation while responding effectively to sustained overloads and short circuits. This helps reduce unnecessary fuse operation while limiting the fault energy passed to downstream conductors and equipment.

With a rated current of 450 A and a voltage rating of 600 V AC / 400 V DC, the AJT450 is suitable for high-current industrial power distribution and equipment protection. Its compact Class J construction and blade terminals support secure installation in compatible fuse clips, fuse holders and fused disconnect switches.

Key Advantages

  • High-capacity Class J time-delay fuse for industrial circuit protection.
  • 450 A current rating for demanding power distribution applications.
  • 600 V AC / 400 V DC voltage rating.
  • Time-delay performance accommodates normal motor and transformer inrush currents.
  • Current-limiting operation helps reduce thermal and mechanical fault damage.
  • Compact Class J footprint supports space-efficient panel designs.

Key Features

  • Mersen Amp-Trap 2000® AJT series.
  • 450 A rated current.
  • 600 V AC / 400 V DC rated voltage.
  • Class J time-delay fuse construction.
  • Blade-terminal configuration.
  • 200 kA AC interrupting rating.
  • Advanced current-limiting protection.
  • Suitable for motor, transformer, feeder and branch circuit applications.
  • Designed for compatible Class J fuse holders and fused disconnects.

Reliable Protection for High-Current Industrial Systems

The Mersen AJT450 helps protect motors, transformers, switchgear, conductors and distribution equipment by interrupting dangerous overcurrents before excessive fault energy can cause serious damage. Its time-delay response permits normal temporary start-up currents without compromising protection against sustained electrical faults.

During a high-level short circuit, the fuse's current-limiting characteristics help reduce the peak current and let-through energy experienced by downstream components. This can minimise equipment damage, lower electrical stress and support improved system reliability in demanding industrial environments.

Typical Applications

  • Main and feeder circuit protection.
  • High-current motor branch circuits.
  • Industrial transformer protection.
  • Motor control centres.
  • Switchboards and distribution panels.
  • OEM machinery and automation systems.
  • Industrial fused disconnect switches.

Technical Specifications

Current 450 A
Voltage 600 V
Item number AJT450
Description Fuse AJT - Class J - Time-delay 600VAC 500VDC 450A Blade SmartSpot® Amp-Trap 2000®
EAN/UPC Code 782001962180
Rated voltage AC UL 600 V
Rated voltage DC UL 500 V
Frequency (Hz) 50/60 Hz
Ampere Rating 450 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 Brass
Connection/Terminal Type Blade
Product Diameter 63.5 mm
Product Length 203.2 mm
Sell Pack Quantity 1 EA
Sell Pack Weight 1.4379 kg
Sell Pack Width 63.5 mm
Sell Pack Length 222.2 mm
Sell Pack Height 60.5 mm
Product group Low Voltage UL/CSA Fuses
Body/Insulating Material GMG
Product Weight 1.3698 kg
HS Code 85361090
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Time delay

Frequently Asked Questions

What is the Mersen AJT450 used for?

The AJT450 is used to protect high-current industrial main, feeder, motor, transformer and branch circuits against sustained overloads and short-circuit faults.

What is the current rating of the AJT450?

The Mersen AJT450 has a rated current of 450 A.

What voltage is the AJT450 rated for?

The AJT450 is rated for operation at up to 600 V AC and 400 V DC.

Can the AJT450 handle motor starting currents?

Yes. Its time-delay characteristics allow normal temporary motor-starting and transformer-energisation currents while maintaining dependable protection against sustained overloads and short circuits.

What is the interrupting rating of the AJT450?

The AJT450 has an AC interrupting rating of 200 kA, making it suitable for installations with high available fault currents.

Where is the Mersen AJT450 typically installed?

It is commonly installed in industrial switchboards, motor control centres, machinery and power distribution equipment using compatible Class J fuse holders or fused disconnect switches.

Trusted for Industrial Circuit Protection

Mersen Amp-Trap 2000® AJT Class J fuses are widely selected by electrical engineers, panel builders and equipment manufacturers for dependable time-delay operation, high interrupting capacity and effective current limitation.

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