MERSEN FUSE 600V 300A CLASS J TD FUSE AJT300

MERSEN FUSE 600V 300A CLASS J TD FUSE AJT300

The Reducer Fuse AJT300 delivers reliable circuit protection with its Class J time-delay design, supporting both 600VAC and 500VDC operations up to 300A. Its blade-type construction ensures easy installation and secure connectivity in industrial panel boards and control systems.

SKU: AJT300MPN: AJT300
Price
List Price £400.04 ex VAT
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£400.04
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Manufacturer Lead Time

£400.04

Why Choose the Mersen AJT300 Class J Time-Delay Fuse?

The Mersen AJT300 is a high-performance Class J time-delay fuse designed to provide reliable overcurrent protection for demanding industrial electrical systems. As part of the advanced Mersen Amp-Trap 2000® AJT series, it combines time-delay operation with superior current-limiting performance, making it suitable for main circuits, feeders and branch circuits serving a wide range of electrical loads.

This fuse is engineered to withstand temporary motor-starting and transformer inrush currents while responding effectively to sustained overloads and short circuits. Its advanced material technology supports IEC Type 2 No Damage protection, helping reduce the risk of costly damage to contactors, motor starters and other connected equipment during fault conditions.

With a rated current of 300 A and a 600 V AC / 400 V DC rating, the AJT300 is ideal for high-current industrial distribution, motor protection and machinery applications. Its compact Class J format requires approximately half the mounting space of comparable 600 V AC Class RK fuses, while its blade terminals support secure installation in compatible fuse clips, holders and fused disconnect switches.

Key Advantages

  • High-capacity Class J time-delay fuse for industrial circuit protection.
  • 300 A current rating suitable for demanding power distribution applications.
  • 600 V AC and 400 V DC voltage rating.
  • Time-delay characteristics accommodate motor and transformer inrush currents.
  • Superior current-limiting performance helps minimise equipment damage.
  • Compact design requires less mounting space than comparable Class RK fuses.

Key Features

  • Mersen Amp-Trap 2000® AJT series.
  • 300 A ampere rating.
  • 600 V AC / 400 V DC rated voltage.
  • Class J time-delay fuse construction.
  • Blade terminal connection.
  • 200 kA AC interrupting rating.
  • Supports IEC Type 2 No Damage protection.
  • Suitable for clip or bolted mounting.

Reliable Protection for High-Current Industrial Systems

The Mersen AJT300 protects electrical equipment by interrupting dangerous overload and short-circuit currents before they can cause extensive thermal or mechanical damage. Its time-delay performance allows normal temporary surges from motors, transformers and other inductive loads to pass without unnecessary fuse operation.

The fuse’s high interrupting capacity and current-limiting characteristics make it suitable for industrial systems with substantial available fault current. Its compact Class J construction also helps panel builders and equipment manufacturers create smaller, more efficient electrical assemblies without compromising protection.

Typical Applications

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

Technical Specifications

Current 300 A
Voltage 600 V
Item number AJT300/600
Description Reducer Fuse AJT - Class J - Time-delay 600VAC 500VDC 300A Blade
EAN/UPC Code 782001463892
Rated voltage AC UL 600 V
Rated voltage DC UL 500 V
Frequency (Hz) 50/60 Hz
Ampere Rating 300 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
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 1.5467 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 1.4742 kg
HS Code 85361090
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Time delay

Frequently Asked Questions

What is the Mersen AJT300 used for?

The AJT300 protects high-current industrial main, feeder and branch circuits against sustained overloads and short-circuit faults.

What is the current rating of the AJT300?

The fuse has a rated current of 300 A.

What voltage is the AJT300 rated for?

The AJT300 is rated for operation at up to 600 V AC and 400 V DC.

Can the AJT300 handle motor starting currents?

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

How is the Mersen AJT300 installed?

The fuse uses blade terminals and can be installed using compatible Class J fuse clips, bolted connections, fuse holders or fused disconnect switches.

Trusted for Industrial Circuit Protection

Mersen Amp-Trap 2000® AJT Class J fuses are widely specified by electrical engineers, panel builders and industrial equipment manufacturers for reliable time-delay protection, high interrupting capacity and excellent current-limiting performance.

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