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MERSEN FUSE 600V 125A CLASS J TD FUSE AJT125
The AJT125 fuse provides reliable overcurrent protection for demanding industrial applications, featuring a time-delay characteristic, SmartSpot® visual indicator, and Amp-Trap 2000® technology for high interrupting capacity.
£99.89
Why Choose the Mersen AJT125 Class J Time-Delay Fuse?
The Mersen AJT125 is a high-performance Class J time-delay fuse designed to provide reliable overcurrent protection for industrial and commercial electrical systems. Part of the proven Mersen Amp-Trap 2000® AJT series, it combines effective current limitation with time-delay characteristics that accommodate temporary motor-starting and transformer inrush currents.
Engineered for demanding branch circuit and feeder applications, the AJT125 helps protect motors, transformers, distribution equipment and industrial machinery against damaging overloads and short circuits. Its compact Class J format supports space-efficient electrical panel designs while providing a high interrupting capacity for dependable operation under severe fault conditions.
With a rated current of 125 A and voltage ratings of up to 600 V AC and 400 V DC, the AJT125 is suitable for motor control centres, switchboards, power distribution systems and OEM machinery. Its blade-style construction enables secure installation in compatible Class J fuse holders and disconnect equipment.
Key Advantages
- Heavy-duty Class J time-delay fuse for industrial circuit protection.
- 125 A current rating for feeders, motors and distribution equipment.
- 600 V AC and 400 V DC voltage ratings.
- Time-delay performance accommodates temporary motor and transformer inrush currents.
- Current-limiting design helps reduce damage to downstream equipment during faults.
- Compact Class J construction supports space-efficient panel layouts.
Key Features
- Mersen Amp-Trap 2000® AJT series.
- 125 A current rating.
- 600 V AC / 400 V DC rated voltage.
- Class J time-delay fuse.
- Blade-style terminal configuration.
- Advanced current-limiting construction.
- SmartSpot® visual open-fuse indication.
- Suitable for branch circuits, feeders, motors and transformers.
Reliable Protection for Industrial Electrical Systems
The Mersen AJT series is designed to tolerate the temporary inrush currents produced by motors, transformers and other inductive loads while responding effectively to sustained overloads and high short-circuit currents. This performance helps prevent nuisance fuse operation without compromising equipment protection.
The AJT125 limits the amount of fault energy passed through to downstream components, helping reduce thermal and mechanical stress on conductors, contactors and electrical equipment. This can improve system safety, minimise damage and reduce costly production downtime.
Typical Applications
- Industrial motor control centres.
- Branch circuits and electrical feeders.
- Transformer protection.
- Power distribution panels and switchboards.
- HVAC and refrigeration equipment.
- OEM machinery and industrial automation systems.
Technical Specifications
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| Fuse Indication | Visual indicator | |
|---|---|---|
| Current | 125 A | |
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| Item number | AJT125 | |
| Description | Fuse AJT - Class J - Time-delay 600VAC 500VDC 125A Blade SmartSpot® Amp-Trap 2000® | |
| EAN/UPC Code | 782001962616 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 500 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 125 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 | |
| Indication System | Yes | |
| Indication System Type | SmartSpot® | |
| Connection/Terminal Material | Brass | |
| Connection/Terminal Type | Blade | |
| Product Diameter | 41.3 mm | |
| Product Length | 146 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 0.3629 kg | |
| Sell Pack Width | 42.9 mm | |
| Sell Pack Length | 42.9 mm | |
| Sell Pack Height | 152.4 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 0.3465 kg | |
| HS Code | 85361090 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen AJT125 used for?
The AJT125 protects industrial branch circuits, feeders, motors, transformers and power distribution equipment against overloads and short circuits.
What is the current rating of the AJT125?
The Mersen AJT125 has a rated current of 125 A.
What voltage is the AJT125 rated for?
The fuse is rated for applications up to 600 V AC and 400 V DC.
Why does the AJT125 have a time delay?
The time-delay characteristic allows temporary starting and inrush currents from motors and transformers without unnecessary fuse operation, while maintaining protection against sustained overloads.
Does the AJT125 include a blown-fuse indicator?
Yes. The AJT125 incorporates a SmartSpot® visual open-fuse indicator to assist with maintenance and fault identification.
Trusted by Electrical Professionals Worldwide
Mersen Amp-Trap 2000® Class J fuses are widely specified by electrical engineers, panel builders and industrial maintenance professionals for dependable current limitation, compact installation and reliable overcurrent protection.
