MERSEN FUSE J TD FUSE 600V 40A AJT AJT40

MERSEN FUSE J TD FUSE 600V 40A AJT AJT40

The AJT40 fuse ensures superior circuit protection with its time-delay feature, reliably safeguarding motors and sensitive equipment from overloads and short circuits up to 600VAC and 400VDC. Features SmartSpot® visual blown-fuse indication and Amp-Trap 2000® performance for robust dependability.

SKU: AJT40MPN: AJT40
Price
List Price £48.33 ex VAT
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Sold in packs of 10

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Why Choose the Mersen AJT40 Class J Time-Delay Fuse?

The Mersen AJT40 is a high-performance Class J time-delay fuse designed to provide dependable overcurrent protection for industrial electrical systems. As part of the established Mersen Amp-Trap 2000® AJT series, it combines effective current-limiting performance with time-delay operation, making it suitable for motors, transformers and other loads that produce temporary inrush currents during normal start-up.

The AJT40 helps protect conductors, control equipment and machinery against sustained overloads and short-circuit faults while reducing unnecessary fuse operation. Its compact Class J format supports space-efficient electrical panel designs and provides strong fault-current protection for demanding industrial installations.

With a rated current of 40 A and a 600 V AC / 400 V DC rating, the AJT40 is suitable for motor branch circuits, transformer circuits, feeders, industrial control panels and power distribution equipment. Its blade-terminal construction enables secure installation in compatible Class J fuse holders, fuse clips and fused disconnect switches.

Key Advantages

  • Industrial Class J time-delay fuse for reliable circuit protection.
  • 40 A current rating suitable for machinery and distribution applications.
  • 600 V AC and 400 V DC voltage rating.
  • Time-delay characteristics accommodate temporary motor and transformer inrush currents.
  • Current-limiting performance helps reduce equipment damage during electrical faults.
  • Compact Class J construction conserves valuable control-panel space.

Key Features

  • Mersen Amp-Trap 2000® AJT series.
  • 40 A rated current.
  • 600 V AC / 400 V DC rated voltage.
  • Class J time-delay fuse construction.
  • Blade-terminal connection.
  • 200 kA AC interrupting rating.
  • Current-limiting protection for industrial circuits.
  • Suitable for compatible Class J fuse holders and disconnect switches.

Reliable Protection for Industrial Electrical Systems

The Mersen AJT40 interrupts dangerous overload and short-circuit currents before excessive fault energy can damage wiring, motors, transformers and electrical control equipment. Its time-delay response allows normal temporary surges associated with motor starting and transformer energisation to pass without unnecessary fuse replacement.

Its current-limiting characteristics help reduce thermal and mechanical stress on downstream components during a fault. This makes the AJT40 a dependable choice for industrial control panels, production machinery and power distribution systems where system reliability and equipment protection are essential.

Typical Applications

  • Motor branch circuit protection.
  • Industrial control panels.
  • Transformer primary and secondary circuits.
  • Main and feeder circuits.
  • OEM machinery and automation equipment.
  • Industrial power distribution systems.

Technical Specifications

Current 40 A
Voltage 600 V
Item number AJT40
Description Fuse AJT - Class J - Time-delay 600VAC 400VDC 40A Ferrule SmartSpot® Amp-Trap 2000®
EAN/UPC Code 782001962326
Rated voltage AC UL 600 V
Rated voltage DC UL 400 V
Frequency (Hz) 50/60 Hz
Ampere Rating 40 A
AC or DC AC/DC
Fuse Class Class J
Speed/Characteristic Time Delay
Mounting Clip
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 Ferrule
Product Diameter 27 mm
Product Length 60.5 mm
Sell Pack Quantity 10 EA
Sell Pack Weight 0.7938 kg
Sell Pack Width 62 mm
Sell Pack Length 139.7 mm
Sell Pack Height 55.6 mm
Product group Low Voltage UL/CSA Fuses
Body/Insulating Material GMG
Product Weight 0.0757 kg
HS Code 85361050
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Time delay

Frequently Asked Questions

What is the Mersen AJT40 used for?

The AJT40 protects industrial motors, transformers, feeders, machinery and branch circuits against sustained overloads and short-circuit faults.

What is the current rating of the AJT40?

The fuse has a rated current of 40 A.

What voltage is the AJT40 rated for?

The AJT40 is rated for operation at up to 600 V AC and 400 V DC.

Can the AJT40 withstand motor starting currents?

Yes. Its time-delay characteristics allow it to tolerate normal temporary motor-starting and transformer inrush currents while maintaining protection against sustained faults.

Where is the Mersen AJT40 typically installed?

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

Trusted for Industrial Circuit Protection

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

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