MERSEN FUSE 600V 125A CLASS J FUSE A4J125

MERSEN FUSE 600V 125A CLASS J FUSE A4J125

The A4J125 offers reliable overcurrent protection with fast-acting response, ensuring critical industrial and commercial equipment is safeguarded against short-circuit and overload conditions. Featuring the robust Amp-Trap® blade design, this fuse delivers low let-through energy for enhanced equipment longevity and minimal downtime.

SKU: A4J125MPN: A4J125
Price
List Price £165.53 ex VAT
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£165.53
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Manufacturer Lead Time

£165.53

Why Choose the Mersen A4J125 Amp-Trap 2000 Fuse?

The Mersen A4J125 is a high-performance Class J fast-acting fuse designed to provide dependable overcurrent and short-circuit protection for industrial electrical equipment. As part of the trusted Mersen Amp-Trap 2000 A4J series, this fuse offers rapid fault interruption, excellent current limitation and reliable protection for feeders, distribution circuits and equipment containing non-inductive loads.

The A4J125 combines a compact Class J footprint with a high interrupting capacity, helping protect electrical installations against damaging fault currents. Its current-limiting design reduces the amount of energy passed through to downstream components during a short circuit, helping minimise equipment damage and improve overall system safety.

With a rated current of 125 A and voltage ratings of up to 600 V AC and 500 V DC, the Mersen A4J125 is suitable for demanding commercial and industrial power distribution applications. Its rejection-style Class J dimensions help prevent the installation of fuses with unsuitable voltage or interrupting ratings.

Key Advantages

  • Fast-acting Class J fuse for industrial circuit protection.
  • 125 A current rating for feeders and equipment circuits.
  • Rated for operation at up to 600 V AC.
  • High current-limiting performance reduces damaging let-through energy.
  • Compact Class J construction helps save panel space.
  • High interrupting capacity for demanding industrial fault conditions.

Key Features

  • Mersen Amp-Trap 2000 A4J series.
  • 125 A rated current.
  • 600 V AC voltage rating.
  • 500 V DC voltage rating.
  • Fast-acting, current-limiting fuse operation.
  • Class J rejection-style dimensions.
  • Designed for feeder, branch-circuit and equipment protection.
  • Suitable for industrial and commercial electrical installations.

Reliable Protection for Industrial Electrical Circuits

Current-limiting fuses such as the Mersen A4J125 interrupt high fault currents rapidly and restrict the peak current that reaches downstream equipment. This helps protect conductors, switches, contactors and other electrical components from excessive thermal and mechanical stress during short-circuit conditions.

The A4J series is designed for applications where fast fault response and high interrupting capacity are required. Its compact Class J format allows efficient use of control-panel space while providing dependable protection for modern industrial power distribution systems.

Typical Applications

  • Industrial power distribution systems.
  • Feeder and branch-circuit protection.
  • Electrical control panels and switchboards.
  • Lighting and heating circuits.
  • Resistive and non-inductive electrical loads.
  • Machinery and production equipment.

Technical Specifications

Current 125 A
Voltage 600 V
Item number A4J125
Description Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 125A Blade Amp-Trap®
EAN/UPC Code 782001960346
Rated voltage AC UL 600 V
Rated voltage DC UL 300 V
Frequency (Hz) 50/60 Hz
Ampere Rating 125 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 41.3 mm
Product Length 146 mm
Sell Pack Quantity 1 EA
Sell Pack Weight 0.3583 kg
Sell Pack Width 42.9 mm
Sell Pack Length 42.9 mm
Sell Pack Height 152.4 mm
Product group Low Voltage UL/CSA Fuses
Body/Insulating Material GMG
Product Weight 0.342 kg
HS Code 85361090
Country of Manufacture Mexico
Fuse Type UL class
Fuse Class Fast acting

Frequently Asked Questions

What is the Mersen A4J125 used for?

The Mersen A4J125 is used to protect industrial feeders, branch circuits and electrical equipment against overloads and high short-circuit currents.

What is the current rating of the A4J125 fuse?

The A4J125 has a rated current of 125 A.

What voltage is the Mersen A4J125 rated for?

The fuse is rated for operation at up to 600 V AC and 500 V DC.

Is the A4J125 a time-delay fuse?

No. The A4J125 is a fast-acting Class J fuse intended to interrupt overcurrents quickly. Applications requiring time-delay performance typically use a suitable time-delay fuse series.

What type of fuse holder is required?

The A4J125 should be installed in a correctly rated Class J fuse holder suitable for a 125 A fuse and the applicable system voltage.

Trusted Industrial Circuit Protection

Mersen Amp-Trap 2000 fuses are widely used by electrical engineers, panel builders and maintenance professionals to provide reliable current-limiting protection for industrial power distribution equipment.

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