MERSEN FUSE 600V 350A CLASS J FUSE A4J350

MERSEN FUSE 600V 350A CLASS J FUSE A4J350

The A4J350 fuse offers rapid circuit protection for demanding industrial applications, with a 350A rating and fast-acting response to minimise equipment downtime. Its robust Class J construction is designed for reliable interruption of high fault currents up to 600VAC and 300VDC.

SKU: A4J350MPN: A4J350
Price
List Price £364.38 ex VAT
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£364.38
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Manufacturer Lead Time

£364.38

Why Choose the Mersen A4J350 Amp-Trap Fuse?

The Mersen A4J350 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 proven Mersen Amp-Trap A4J series, it provides rapid fault interruption for feeder circuits, switchboards, panelboards and high-current electrical equipment.

The A4J350 offers excellent current-limiting performance by reducing the peak current and let-through energy passed to downstream components during a fault. This helps minimise thermal and mechanical stress on cables, busbars, switches and other electrical equipment, supporting improved system safety and reduced equipment damage.

With a rated current of 350 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J350 is suitable for demanding AC and DC power-distribution applications. Its Class J rejection dimensions help prevent substitution with fuses that have unsuitable voltage, interrupting or current-limiting characteristics.

Key Advantages

  • Fast-acting Class J fuse for industrial circuit protection.
  • 350 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.
  • 350 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 A4J350 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 dependable current limitation. Its Class J format supports safe fuse selection while providing reliable protection for 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

Current 350 A
Voltage 600 V
Item number A4J350
Description Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 350A Blade Amp-Trap®
EAN/UPC Code 782001960438
Rated voltage AC UL 600 V
Rated voltage DC UL 300 V
Frequency (Hz) 50/60 Hz
Ampere Rating 350 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
Fuse Type UL class
Fuse Class Fast acting

Frequently Asked Questions

What is the Mersen A4J350 used for?

The Mersen A4J350 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 A4J350 fuse?

The A4J350 has a rated current of 350 A.

What voltage is the Mersen A4J350 rated for?

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

Is the A4J350 a time-delay fuse?

No. The A4J350 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 A4J350?

The A4J350 should be installed in a compatible Class J fuse holder rated for a 350 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.

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