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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.
£200.02
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
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| Current | 300 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| 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 |
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.
