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MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 125 A, 600 V AC, 300 V DC - Fast-Acting Bolt-On Fuses
MERSENFast-Acting Bolt-On Fuses

MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 125 A, 600 V AC, 300 V DC

The MERSEN A4J Series is a fast-acting bolt-on fuse with a Class J blade body, rated at 125 A, 600 V AC, and 300 V DC. It is non-indicating and operates as a single-stage device, providing overcurrent protection for…

SKU 3G-OTH-25298

Brand
MERSEN
Item
Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 125 A, 600 V AC, 300 V DC
Category
Fast-Acting Bolt-On Fuses
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

MERSEN
Manufacturer Part Number
A4J125
Series
A4J
Type
Class J, Blade Body, Fast-Acting, 125 A, Non-Indicating
AC
600 V
DC
300 V

Technical Documents

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MERSEN Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MERSEN A4J Series is a fast-acting bolt-on fuse with a Class J blade body, rated at 125 A, 600 V AC, and 300 V DC. It is non-indicating and operates as a single-stage device, providing overcurrent protection for industrial equipment.

Frequently Asked Questions

What is the MERSEN A4J125 fuse used for?

The MERSEN A4J125 is a fast-acting bolt-on fuse used for overcurrent protection in industrial equipment. It is suitable for applications requiring Class J protection, such as motor control centers, panelboards, and branch circuits, where fast response to short circuits is critical.

What are the specifications of the MERSEN A4J125 fuse?

The MERSEN A4J125 is a Class J, blade-body, fast-acting fuse rated at 125 A, 600 V AC, and 300 V DC. It is non-indicating and part of the A4J Series. This single-stage device provides reliable overcurrent protection for industrial systems.

Where to buy MERSEN A4J125 fuses worldwide?

You can source MERSEN A4J125 fuses through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring you receive genuine MERSEN components for your operations.

How to select the correct MERSEN A4J fuse for my application?

To select the correct MERSEN A4J fuse, match the voltage rating (600 V AC or 300 V DC) and current rating (125 A for the A4J125) to your circuit requirements. Ensure the Class J blade body fits your fuse holder. Consult a qualified engineer for specific coordination studies.

Used in

Common applications for MERSEN
Power electronics protection — MERSEN A70Q series semiconductor fuses in variable frequency drives for motor control.
Surge protection for industrial panels — MERSEN STP480D07 SPDs in three-phase 480V AC distribution boards.
Control circuit overcurrent protection — MERSEN ATM series midget fuses in PLC and instrumentation cabinets.
Power distribution in manufacturing — MERSEN FSPDB4A finger-safe blocks in motor control centers for wire management.
DC bus protection in renewable energy — MERSEN A30QS series fuses in solar inverter DC inputs.
High-voltage semiconductor protection — MERSEN A70Q series fuses in welding equipment power supplies.

MERSEN Products

3G Electric supplies MERSEN fast-acting bolt-on fuses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Cross-referenced by specification & description
MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 200 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J200)
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MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 200 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J200)
MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 225 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J225)
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MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 225 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J225)
MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 110 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J110)
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MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 300 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J300)
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MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 300 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J300)
MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 450 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J450)
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MERSEN Fuse: A4J Series, Class J, Blade Body, Fast-Acting, 450 A, 600 V AC, 300 V DC, Non-Indicating (MPN A4J450)

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