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.
