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MERSEN FUSE 600V 300A CLASS J FUSE A4J300
The A4J300 is a fast-acting Class J fuse rated for 300A, 600VAC and 300VDC, featuring Amp-Trap® technology for reliable circuit protection in industrial applications.
£159.51
Why Choose the Mersen A4J300 Amp-Trap Fuse?
The Mersen A4J300 is a high-performance Class J fast-acting current-limiting fuse designed to protect industrial and commercial electrical systems against damaging overcurrents and short circuits. As part of the established Mersen Amp-Trap A4J series, it provides rapid fault interruption for power-distribution equipment, feeder circuits and general industrial loads.
The A4J300 delivers excellent current-limiting performance by reducing the peak current and let-through energy that can reach downstream equipment during a fault. This helps minimise thermal and mechanical stress on conductors, switches, busbars and other electrical components, supporting improved system safety and reduced equipment damage.
With a rated current of 300 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J300 is suitable for demanding AC and DC power-distribution applications. Its Class J rejection dimensions help prevent replacement with fuses that have unsuitable voltage, interrupting or current-limiting characteristics.
Key Advantages
- Fast-acting Class J fuse for industrial circuit protection.
- 300 A current rating for high-current feeders and equipment.
- 600 V AC and 300 V DC ratings for AC and DC systems.
- Current-limiting operation helps reduce damaging fault energy.
- 200 kA AC interrupting rating for high-fault-current installations.
- Class J rejection dimensions help prevent unsuitable fuse substitution.
Key Features
- Mersen Amp-Trap A4J series.
- 300 A rated current.
- 600 V AC voltage rating.
- 300 V DC voltage rating.
- Fast-acting current-limiting performance.
- Blade-terminal construction.
- High interrupting capacity for demanding electrical systems.
- Compatible with correctly rated Class J fuse holders.
Reliable Protection for High-Current Electrical Systems
Current-limiting fuses such as the Mersen A4J300 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 associated with short-circuit conditions.
The A4J series is designed for installations requiring fast operation, high interrupting capacity and reliable current limitation. Its compact Class J format allows efficient use of panel space while maintaining dependable protection in industrial switchboards, distribution panels and machinery installations.
Typical Applications
- Industrial feeder circuits.
- Panelboards and switchboards.
- Load centres and power-distribution equipment.
- Bus duct systems.
- Lighting and heating circuits.
- Industrial machinery and general-purpose electrical loads.
Technical Specifications
Tick the specs you need, then view products that match.
| Current | 300 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Fast acting | |
| Item number | A4J300 | |
| Description | Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 300A Blade Amp-Trap® | |
| EAN/UPC Code | 782001960414 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 300 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 300 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 | 85361090 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4J300 used for?
The Mersen A4J300 provides fast-acting overcurrent and short-circuit protection for industrial feeder circuits, switchboards, panelboards and high-current electrical equipment.
What is the current rating of the A4J300 fuse?
The A4J300 has a rated current of 300 A.
What voltage is the Mersen A4J300 rated for?
The fuse is rated for operation at up to 600 V AC and 300 V DC.
Is the A4J300 a time-delay fuse?
No. The A4J300 is a fast-acting Class J current-limiting fuse designed to interrupt overcurrents and short-circuit faults rapidly.
What fuse holder is required for the A4J300?
The A4J300 should be installed in a compatible Class J fuse holder rated for a 300 A fuse 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 dependable current limitation and high-performance protection in demanding industrial power systems.
