MERSEN FUSE 600V 450A CLASS J FUSE A4J450

MERSEN FUSE 600V 450A CLASS J FUSE A4J450

The Fuse A4J450 Class J fast-acting fuse delivers superior circuit protection for demanding industrial applications, with a robust 600VAC/300VDC voltage rating and a high interrupting capacity.

SKU: A4J450MPN: A4J450
Price
List Price £538.53 ex VAT
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Manufacturer Lead Time

£538.53

Why Choose the Mersen A4J450 Amp-Trap Fuse?

The Mersen A4J450 is a heavy-duty Class J fast-acting current-limiting fuse engineered to provide superior protection against overloads and short circuits in industrial and commercial power distribution systems. As part of the trusted Mersen Amp-Trap A4J series, it delivers rapid fault interruption, exceptional current limitation and dependable protection for high-current electrical installations.

Designed for demanding applications, the A4J450 significantly limits peak fault current and let-through energy, helping to minimise thermal and mechanical stress on downstream equipment such as switchboards, bus duct systems, feeders and industrial machinery. Its Class J rejection dimensions also prevent replacement with lower-rated fuse classes, maintaining system integrity and safety.

With a rated current of 450 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J450 is ideally suited to high-current feeder protection and industrial power distribution systems requiring fast-acting overcurrent protection.

Key Advantages

  • Fast-acting Class J fuse for industrial circuit protection.
  • 450 A current rating for high-current feeders and distribution equipment.
  • 600 V AC and 300 V DC voltage ratings.
  • Current-limiting design reduces damaging fault energy.
  • 200 kA AC interrupting rating and 100 kA DC interrupting rating.
  • Class J rejection dimensions prevent incorrect fuse replacement.

Key Features

  • Mersen Amp-Trap A4J series.
  • 450 A rated current.
  • 600 V AC voltage rating.
  • 300 V DC voltage rating.
  • Fast-acting current-limiting protection.
  • Blade terminal construction.
  • Fibreglass body for excellent dimensional stability.
  • Compatible with Class J fuse holders.

Reliable Protection for High-Current Electrical Systems

The Mersen A4J450 interrupts fault currents within milliseconds, reducing peak current and total let-through energy before damaging levels can be reached. This helps protect transformers, switchgear, busbars, cables and industrial equipment from the destructive effects of high fault currents.

The Amp-Trap A4J range is widely specified in industrial facilities, manufacturing plants and commercial power distribution systems where dependable current limitation and high interrupting capacity are essential.

Typical Applications

  • Industrial feeder circuits.
  • Switchboards and panelboards.
  • Bus duct systems.
  • Load centres.
  • Industrial machinery.
  • General power distribution equipment.

Technical Specifications

Current 450 A
Voltage 600 V
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 85361090
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Fast acting

Frequently Asked Questions

What is the Mersen A4J450 used for?

The Mersen A4J450 provides fast-acting overcurrent and short-circuit protection for high-current industrial feeders, switchboards, bus duct systems and power distribution equipment.

What is the current rating of the A4J450?

The fuse has a 450 A current rating.

What voltage is the Mersen A4J450 rated for?

The A4J450 is rated for operation at up to 600 V AC and 300 V DC.

Is the A4J450 a fast-acting fuse?

Yes. The A4J450 is a fast-acting Class J current-limiting fuse that interrupts overloads and short-circuit faults extremely quickly.

Where is the A4J450 typically installed?

It is commonly installed in Class J fuse holders within industrial switchboards, bus duct systems, load centres and high-current electrical distribution equipment.

Trusted by Electrical Professionals Worldwide

Mersen Amp-Trap Class J fuses are trusted by electrical engineers, OEMs and maintenance professionals for delivering dependable overcurrent protection, excellent current limitation and reliable performance in demanding industrial environments.

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