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MERSEN FUSE J TD FUSE 600V 50A AJT AJT50
The AJT50 fuse delivers superior circuit protection with time-delay characteristics, ensuring reliable safeguarding of inductive loads and critical equipment. Rated for 600VAC and 400VDC at 50A, it features SmartSpot® visual indication and Amp-Trap 2000® design for enhanced arc-quenching.
£24.17
Why Choose the Mersen AJT50 Class J Time-Delay Fuse?
The Mersen AJT50 is a high-performance Class J time-delay fuse designed to provide reliable overcurrent protection for industrial electrical systems. As part of the proven Mersen Amp-Trap 2000® AJT series, it combines time-delay operation with superior current-limiting capability, making it suitable for motors, transformers, feeders and branch circuits that experience temporary inrush currents during normal operation.
The AJT50 is engineered to tolerate typical motor-starting and transformer-energisation currents while responding effectively to sustained overloads and short circuits. Its compact Class J construction requires approximately half the mounting space of comparable 600 V AC Class RK fuses, helping panel builders and equipment manufacturers create space-efficient electrical assemblies without compromising protection.
With a rated current of 50 A and a voltage rating of 600 V AC / 400 V DC, the AJT50 is suitable for industrial machinery, motor branch circuits, transformer protection and power distribution equipment. Its ferrule terminals provide a secure connection in compatible Class J fuse clips, holders and fused disconnect switches.
Key Advantages
- Industrial Class J time-delay fuse for dependable overcurrent protection.
- 50 A current rating for motor, transformer and distribution circuits.
- 600 V AC / 400 V DC voltage rating.
- Time-delay characteristics accommodate normal motor and transformer inrush currents.
- Current-limiting performance helps reduce thermal and mechanical damage during faults.
- Compact Class J footprint helps conserve valuable panel space.
Key Features
- Mersen Amp-Trap 2000® AJT series.
- 50 A rated current.
- 600 V AC / 400 V DC rated voltage.
- Class J time-delay fuse construction.
- Ferrule terminal configuration.
- 200 kA AC interrupting rating.
- Tin-plated copper terminal material.
- Supports IEC Type 2 No Damage protection.
- Available with non-indicating or SmartSpot® visual indication options within the AJT range.
- RoHS-compliant construction.
Reliable Protection for Industrial Electrical Systems
The Mersen AJT50 helps protect conductors, motors, transformers and electrical equipment by interrupting dangerous overload and short-circuit currents before excessive fault energy can cause serious damage. Its time-delay response allows temporary start-up currents to pass without unnecessary fuse operation, helping improve equipment availability and reduce maintenance.
During high-level faults, the fuse's current-limiting characteristics reduce the peak current and let-through energy experienced by downstream components. This can help minimise thermal stress, mechanical forces and equipment damage in demanding industrial environments.
Typical Applications
- Motor branch circuit protection.
- Transformer primary and secondary circuits.
- Main and feeder circuit protection.
- Industrial control panels.
- OEM machinery and automation equipment.
- Fused disconnect switches.
- Industrial power distribution systems.
Technical Specifications
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| Fuse Indication | Visual indicator | |
|---|---|---|
| Current | 50 A | |
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| Item number | AJT50 | |
| Description | Fuse AJT - Class J - Time-delay 600VAC 400VDC 50A Ferrule SmartSpot® Amp-Trap 2000® | |
| EAN/UPC Code | 782001962364 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 400 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 50 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 |
Frequently Asked Questions
What is the Mersen AJT50 used for?
The AJT50 protects industrial motors, transformers, feeders, branch circuits and electrical machinery against sustained overloads and short-circuit faults.
What is the current rating of the AJT50?
The Mersen AJT50 has a rated current of 50 A.
What voltage is the AJT50 rated for?
The AJT50 is rated for operation at up to 600 V AC and 400 V DC.
Can the AJT50 handle motor starting currents?
Yes. Its time-delay characteristics allow normal temporary motor-starting and transformer inrush currents while maintaining dependable protection against sustained overloads and short circuits.
What type of terminals does the AJT50 use?
The AJT50 uses ferrule terminals manufactured from tin-plated copper for installation in compatible Class J fuse clips and holders.
What are the dimensions of the Mersen AJT50?
The fuse measures approximately 60.5 mm in length and 27 mm in diameter.
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 reliable time-delay protection, high interrupting capacity and effective current limitation.
