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MERSEN FUSE 600V 25A CLASS J FUSE A4J25
Fast-acting Class J blade fuse rated for 600VAC and 300VDC with 250A rating and 200 kA breaking capacity, suitable for industrial motor and control panel protection.
£18.17
Why Choose the Mersen A4J25 Amp-Trap Fuse?
The Mersen A4J25 is a compact, fast-acting Class J current-limiting fuse designed to protect industrial and commercial electrical systems against damaging overcurrents and short circuits. Part of the trusted Mersen Amp-Trap A4J series, it combines rapid fault interruption with a high breaking capacity for dependable protection of feeders, branch circuits and electrical equipment.
The A4J25 is engineered to limit the peak current and let-through energy reaching downstream components during a fault. This helps reduce thermal and mechanical stress on conductors, switches, contactors and other equipment, supporting improved system reliability and reduced risk of costly electrical damage.
With a rated current of 25 A, a 600 V AC rating and a 300 V DC rating, the A4J25 is suitable for a wide range of power distribution and equipment-protection applications. Its unique Class J dimensions help prevent substitution with fuses offering lower voltage, interrupting or current-limiting ratings.
Key Advantages
- Fast-acting Class J fuse for industrial circuit protection.
- 25 A current rating for feeders, branch circuits and equipment.
- 600 V AC and 300 V DC ratings for AC and DC applications.
- Excellent current limitation helps reduce damaging fault energy.
- 200 kA AC breaking capacity for high-fault-current systems.
- Unique Class J dimensions help prevent unsuitable fuse substitution.
Key Features
- Mersen Amp-Trap A4J series.
- 25 A rated current.
- 600 V AC voltage rating.
- 300 V DC voltage rating.
- Fast-acting current-limiting operation.
- Tin-plated copper ferrule terminals.
- Compact cylindrical PolyTube body.
- Clip mounting in a compatible Class J fuse holder.
Reliable Protection for Industrial Electrical Circuits
Current-limiting fuses such as the Mersen A4J25 interrupt fault currents rapidly before they can reach their maximum prospective level. By restricting peak current and total let-through energy, the fuse helps protect downstream equipment from excessive heat, electromagnetic forces and other damaging effects of short-circuit conditions.
The A4J series is designed for electrical installations requiring a compact fuse with fast operation, high interrupting capability and reliable current limitation. Its Class J format makes it suitable for modern control panels and distribution systems where space efficiency and dependable circuit protection are essential.
Typical Applications
- Industrial electrical control panels.
- Feeder and branch-circuit protection.
- Panelboards and switchboards.
- Lighting and heating circuits.
- Power distribution equipment.
- Machinery and general industrial loads.
Technical Specifications
Tick the specs you need, then view products that match.
| Current | 25 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Fast acting | |
| Item number | A4J250 | |
| Description | Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 250A Blade Amp-Trap® | |
| EAN/UPC Code | 782001960391 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 300 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 250 A | |
| AC or DC | AC/DC | |
| Fuse Class | Class J | |
| Speed/Characteristic | Fast-Acting | |
| Mounting | Clip | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Connection/Terminal Material | Brass Alloy | |
| Connection/Terminal Type | Blade | |
| Product Diameter | 54 mm | |
| Product Length | 181.1 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 0.8346 kg | |
| Sell Pack Width | 53.8 mm | |
| Sell Pack Length | 53.8 mm | |
| Sell Pack Height | 184.1 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 0.7938 kg | |
| HS Code | 85361050 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4J25 used for?
The Mersen A4J25 provides fast-acting overcurrent and short-circuit protection for feeders, branch circuits, control panels and industrial electrical equipment.
What is the current rating of the A4J25 fuse?
The A4J25 has a rated current of 25 A.
What voltage is the Mersen A4J25 rated for?
The fuse is rated for operation at up to 600 V AC and 300 V DC.
Is the A4J25 a time-delay fuse?
No. The A4J25 is a fast-acting Class J fuse designed to interrupt overloads and short-circuit currents rapidly.
What fuse holder is required for the A4J25?
The A4J25 should be installed in a compatible Class J fuse holder rated for at least 25 A and the applicable system voltage.
Trusted Industrial Circuit Protection
Mersen Amp-Trap Class J fuses are widely specified by electrical engineers, panel builders and maintenance professionals for reliable current limitation and high-performance protection in demanding electrical systems.
