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MERSEN FUSE 600V 45A CLASS J FUSE A4J45
The Fuse A4J45 delivers rapid circuit protection for critical applications, ensuring safe and reliable interruption of overcurrents up to 450A. Its fast-acting design is ideal for safeguarding sensitive power distribution systems and equipment operating at 600VAC or 300VDC.
£29.65
Why Choose the Mersen A4J45 Amp-Trap Fuse?
The Mersen A4J45 is a premium Class J fast-acting current-limiting fuse designed to provide reliable protection against overloads and short circuits in industrial and commercial electrical systems. As part of the trusted Mersen Amp-Trap A4J series, it delivers rapid fault interruption and outstanding current-limiting performance for branch circuits, feeders and electrical equipment.
Designed for demanding industrial applications, the A4J45 limits peak fault current and let-through energy, helping to protect downstream equipment from excessive thermal and mechanical stress. Its unique Class J rejection dimensions prevent substitution with lower-rated fuse classes, improving electrical safety and ensuring compliance with modern installations.
With a rated current of 45 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J45 is ideal for protecting panelboards, switchboards, load centres, industrial machinery and general-purpose electrical loads requiring dependable fast-acting protection.
Key Advantages
- Fast-acting Class J fuse for industrial circuit protection.
- 45 A current rating for branch circuits and industrial equipment.
- 600 V AC and 300 V DC voltage ratings.
- High current-limiting design reduces damaging fault energy.
- 200 kA AC interrupting capacity for demanding installations.
- Class J rejection dimensions prevent incorrect fuse replacement.
Key Features
- Mersen Amp-Trap A4J series.
- 45 A rated current.
- 600 V AC voltage rating.
- 300 V DC voltage rating.
- Fast-acting current-limiting protection.
- Ferrule terminal construction.
- Fibreglass body provides excellent dimensional stability.
- Compatible with Class J fuse holders.
Reliable Protection for Industrial Electrical Systems
Current-limiting fuses such as the Mersen A4J45 interrupt fault currents extremely quickly, reducing peak let-through current and thermal energy before they can damage downstream equipment. This helps improve system reliability, reduce maintenance costs and minimise costly downtime.
The Amp-Trap A4J series is widely specified for industrial control panels, switchboards, feeder circuits, bus duct systems and load centres where dependable circuit protection and high interrupting capacity are essential.
Typical Applications
- Industrial control panels.
- Panelboards and switchboards.
- Load centres.
- Feeder and branch circuit protection.
- Lighting and heating circuits.
- General industrial machinery.
Technical Specifications
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| Current | 45 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Fast acting | |
| Item number | A4J450 | |
| Description | Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 450A Blade Amp-Trap® | |
| EAN/UPC Code | 782001960476 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 300 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 450 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 | 63.5 mm | |
| Product Length | 203.2 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 1.4379 kg | |
| Sell Pack Width | 63.5 mm | |
| Sell Pack Length | 222.2 mm | |
| Sell Pack Height | 60.5 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 1.3698 kg | |
| HS Code | 85361050 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4J45 used for?
The Mersen A4J45 provides fast-acting overcurrent and short-circuit protection for industrial power distribution systems, feeders, branch circuits and electrical equipment.
What is the current rating of the A4J45?
The fuse has a 45 A current rating.
What voltage is the Mersen A4J45 rated for?
The A4J45 is rated for operation at up to 600 V AC and 300 V DC.
Is the A4J45 a fast-acting fuse?
Yes. The A4J45 is a fast-acting Class J current-limiting fuse designed to interrupt overloads and short-circuit faults rapidly.
Where is the A4J45 typically installed?
It is commonly installed in Class J fuse holders within industrial control panels, switchboards, load centres and power distribution equipment.
Trusted by Electrical Professionals Worldwide
Mersen Amp-Trap Class J fuses are trusted by electrical engineers, OEMs and maintenance professionals for dependable circuit protection, exceptional current limitation and reliable performance in demanding industrial applications.
