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MERSEN FUSE J TD FUSE 600V 25A AJT AJT25
Heavy-duty 25A time-delay fuse with Amp-Trap 2000® technology and SmartSpot® visual indicator for superior circuit protection up to 600VAC and 400VDC.
£14.22
Why Choose the Mersen AJT25 Class J Time-Delay Fuse?
The Mersen AJT25 is a high-performance Class J time-delay fuse designed to deliver dependable overcurrent protection for industrial and commercial electrical systems. As part of the proven Amp-Trap 2000® AJT series, it combines advanced current-limiting technology with controlled time-delay characteristics that accommodate temporary motor-starting and transformer energisation currents while providing fast interruption during fault conditions.
Designed for branch circuits, feeders and motor protection, the AJT25 safeguards motors, transformers, control panels, switchgear and industrial machinery against damaging overloads and short circuits. Its compact Class J construction requires approximately half the mounting space of comparable 600 V Class RK fuses, making it ideal for space-constrained electrical installations.
With a rated current of 25 A, voltage ratings of 600 V AC and 400 V DC, and a high interrupting capacity, the AJT25 is well suited to industrial control systems, OEM machinery, HVAC equipment and electrical distribution panels. The standard AJT25 incorporates Mersen's SmartSpot® visual open-fuse indicator for quicker fault identification during maintenance.
Key Advantages
- High-performance Class J time-delay fuse for industrial protection.
- 25 A current rating for branch circuits, feeders and motor applications.
- 600 V AC / 400 V DC voltage ratings.
- Time-delay characteristics accommodate motor and transformer inrush currents.
- Advanced current-limiting technology reduces fault energy.
- Compact Class J dimensions require significantly less panel space than comparable Class RK fuses.
Key Features
- Mersen Amp-Trap 2000® AJT series.
- 25 A current rating.
- 600 V AC / 400 V DC rated voltage.
- Class J time-delay fuse.
- Ferrule terminal construction.
- SmartSpot® visual blown-fuse indication.
- High current-limiting capability.
- Suitable for all load types including motors and transformers.
Reliable Protection for Industrial Electrical Systems
The AJT25 is engineered to withstand the temporary inrush currents associated with motor starting and transformer energisation while rapidly interrupting sustained overloads and short-circuit faults. This helps minimise nuisance fuse operation and supports improved equipment availability.
Its advanced current-limiting design significantly reduces thermal and mechanical stress on downstream conductors, contactors and switchgear during severe fault conditions, helping improve electrical safety and reduce maintenance costs.
Typical Applications
- Industrial control panels.
- Motor branch circuits.
- Transformer protection.
- Electrical feeders.
- HVAC and refrigeration systems.
- OEM machinery.
- Industrial automation equipment.
- Power distribution systems.
Technical Specifications
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| Fuse Indication | Visual indicator | |
|---|---|---|
| Current | 25 A | |
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| Item number | AJT25 | |
| Description | Fuse AJT - Class J - Time-delay 600VAC 400VDC 25A Ferrule SmartSpot® Amp-Trap 2000® | |
| EAN/UPC Code | 782001962425 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 400 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 25 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 | 20.7 mm | |
| Product Length | 57.2 mm | |
| Sell Pack Quantity | 10 EA | |
| Sell Pack Weight | 0.4627 kg | |
| Sell Pack Width | 60.5 mm | |
| Sell Pack Length | 111.3 mm | |
| Sell Pack Height | 42.9 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 0.044 kg | |
| HS Code | 85361050 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen AJT25 used for?
The AJT25 protects industrial branch circuits, motors, transformers, feeders and control equipment against overloads and short circuits.
What is the current rating of the AJT25?
The Mersen AJT25 has a rated current of 25 A.
What voltage is the AJT25 rated for?
The fuse is rated for applications up to 600 V AC and 400 V DC.
Does the AJT25 include a blown-fuse indicator?
Yes. The standard AJT25 includes Mersen's SmartSpot® visual open-fuse indicator for fast fault identification.
Why is the AJT25 suitable for motor circuits?
Its time-delay characteristics allow normal motor-starting current and transformer inrush currents to pass without nuisance operation while maintaining excellent protection against sustained overloads and short circuits.
Trusted by Electrical Professionals Worldwide
Mersen Amp-Trap 2000® Class J fuses are trusted by electrical engineers, panel builders and maintenance professionals for compact installation, reliable current limitation and dependable overcurrent protection.
