MERSEN FUSE 600V 3A CLASS J FUSE A4J3

MERSEN FUSE 600V 3A CLASS J FUSE A4J3

The Fuse A4J offers superior short-circuit protection with fast-acting response characteristics and a robust 600VAC, 300VDC, 3A rating. Its compact ferrule design ensures easy integration into demanding control panels and distribution systems.

SKU: A4J3MPN: A4J3
Price
List Price £36.34 ex VAT
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Manufacturer Lead Time

Sold in packs of 10

£36.34

Why Choose the Mersen A4J3 Amp-Trap Fuse?

The Mersen A4J3 is a compact and dependable Class J fast-acting current-limiting fuse designed to protect industrial and commercial electrical circuits against overloads and short circuits. As part of the established Mersen Amp-Trap A4J series, it provides rapid fault interruption and reliable protection for branch circuits, control panels and sensitive electrical equipment.

The A4J3 limits 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 electrical devices, improving system safety and helping minimise equipment damage and unplanned downtime.

With a rated current of 3 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J3 is suitable for low-current industrial circuits requiring high interrupting capacity. Its compact Class J dimensions also help prevent substitution with fuses that have unsuitable voltage, interrupting or current-limiting ratings.

Key Advantages

  • Fast-acting Class J fuse for industrial circuit protection.
  • 3 A current rating for low-current branch circuits and equipment.
  • 600 V AC and 300 V DC ratings for AC and DC applications.
  • Current-limiting performance helps reduce damaging fault energy.
  • 200 kA AC interrupting capacity for high-fault-current systems.
  • Class J rejection dimensions help prevent unsuitable fuse substitution.

Key Features

  • Mersen Amp-Trap A4J series.
  • 3 A rated current.
  • 600 V AC voltage rating.
  • 300 V DC voltage rating.
  • Fast-acting current-limiting operation.
  • Ferrule-style terminals for secure installation.
  • Compact cylindrical cartridge construction.
  • Compatible with correctly rated Class J fuse holders.

Reliable Protection for Low-Current Industrial Circuits

Current-limiting fuses such as the Mersen A4J3 interrupt high fault currents 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 fault response, high interrupting capacity and compact dimensions. Its Class J construction makes the A4J3 suitable for modern control panels and electrical distribution systems where reliable protection and efficient use of enclosure space are essential.

Typical Applications

  • Industrial electrical control panels.
  • Low-current branch circuits.
  • Lighting and heating circuits.
  • Power distribution equipment.
  • Instrumentation and control equipment.
  • Machinery and general industrial loads.

Technical Specifications

Current 3 A
Voltage 600 V
Item number A4J3
Description Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 3A Ferrule Amp-Trap®
EAN/UPC Code 782001960063
Rated voltage AC UL 600 V
Rated voltage DC UL 300 V
Frequency (Hz) 50/60 Hz
Ampere Rating 3 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 85361010
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Fast acting

Frequently Asked Questions

What is the Mersen A4J3 used for?

The Mersen A4J3 provides fast-acting overcurrent and short-circuit protection for low-current branch circuits, control panels and industrial electrical equipment.

What is the current rating of the A4J3 fuse?

The A4J3 has a rated current of 3 A.

What voltage is the Mersen A4J3 rated for?

The fuse is rated for operation at up to 600 V AC and 300 V DC.

Is the A4J3 a time-delay fuse?

No. The A4J3 is a fast-acting Class J fuse designed to interrupt overcurrents and short-circuit faults rapidly.

What fuse holder is required for the A4J3?

The A4J3 should be installed in a compatible Class J fuse holder rated for a 3 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 industrial electrical systems.

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