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MERSEN FUSE 600V 20A CLASS J FUSE A4J20
Fast-acting Class J fuse with 20A rating, suitable for 600VAC and 300VDC applications. Features ferrule terminals and a PolyTube insulating body for reliable circuit protection.
£15.98
Why Choose the Mersen A4J20 Amp-Trap 2000 Fuse?
The Mersen A4J20 is a high-performance Class J fast-acting fuse engineered to provide reliable overcurrent and short-circuit protection for industrial and commercial electrical systems. As part of the trusted Mersen Amp-Trap 2000 A4J series, it delivers exceptional current-limiting performance, helping to safeguard electrical equipment while reducing damage caused by fault currents.
Designed for applications requiring rapid fault interruption, the A4J20 helps protect sensitive electrical components, feeders and branch circuits from overloads and high prospective short-circuit currents. Its unique Class J dimensions prevent substitution with lower-rated fuse types, improving overall system safety and compliance.
With a rated current of 20 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J20 is well suited to industrial control panels, switchboards, lighting circuits and general-purpose electrical distribution systems.
Key Advantages
- Fast-acting Class J fuse for industrial circuit protection.
- 20 A current rating for branch circuits and electrical equipment.
- 600 V AC and 300 V DC ratings.
- High current-limiting capability reduces let-through energy.
- Compact Class J rejection design improves installation safety.
- High interrupting capacity for demanding industrial environments.
Key Features
- Mersen Amp-Trap 2000 A4J series.
- 20 A rated current.
- 600 V AC voltage rating.
- 300 V DC voltage rating.
- Fast-acting current-limiting operation.
- Ferrule terminal construction.
- Class J rejection-style design.
- Suitable for industrial power distribution and equipment protection.
Reliable Protection for Industrial Electrical Systems
Current-limiting fuses such as the Mersen A4J20 interrupt fault currents extremely quickly, reducing peak current and limiting thermal and mechanical stress on downstream equipment. This helps improve equipment reliability while reducing maintenance costs and unplanned downtime.
The Amp-Trap 2000 A4J series is widely specified by electrical engineers and panel builders for installations requiring dependable protection, high interrupting ratings and compliance with recognised industry standards.
Typical Applications
- Industrial control panels.
- Power distribution systems.
- Panelboards and switchboards.
- Lighting and heating circuits.
- General industrial electrical equipment.
- Feeder and branch-circuit protection.
Technical Specifications
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| Current | 20 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Fast acting | |
| Item number | A4J20 | |
| Description | Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 20A Ferrule Amp-Trap® | |
| EAN/UPC Code | 782001960162 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 300 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 20 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 | Tin-Plated Copper | |
| Connection/Terminal Type | Ferrule | |
| Product Diameter | 20.7 mm | |
| Product Length | 57.2 mm | |
| Sell Pack Quantity | 10 EA | |
| Sell Pack Weight | 0.4627 kg | |
| Sell Pack Width | 60.5 mm | |
| Sell Pack Length | 108 mm | |
| Sell Pack Height | 42.9 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | PolyTube | |
| Product Weight | 0.044 kg | |
| HS Code | 85361050 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4J20 used for?
The Mersen A4J20 provides fast-acting overcurrent and short-circuit protection for industrial electrical circuits, panelboards, switchboards and general-purpose equipment.
What is the current rating of the A4J20?
The fuse has a 20 A current rating.
What voltage is the Mersen A4J20 rated for?
The A4J20 is rated for up to 600 V AC and 300 V DC.
Is the A4J20 a fast-acting fuse?
Yes. The A4J20 is a fast-acting Class J current-limiting fuse designed for rapid interruption of overloads and short-circuit faults.
Where is the A4J20 typically installed?
It is commonly installed in Class J fuse holders within industrial control panels, switchboards, panelboards and power distribution equipment.
Trusted by Electrical Professionals Worldwide
Mersen Amp-Trap 2000 Class J fuses are trusted by electrical engineers, OEMs and maintenance professionals for dependable circuit protection, high interrupting capacity and reliable performance in demanding industrial applications.
