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MERSEN Fuse: A4J Series, Class J, Cylindrical Body, Fast-Acting, 40 A, 600 V AC - Fast-Acting Cylindrical Fuses
MERSENFast-Acting Cylindrical Fuses

MERSEN Fuse: A4J Series, Class J, Cylindrical Body, Fast-Acting, 40 A, 600 V AC

The MERSEN A4J Series is a fast-acting cylindrical fuse, specifically a Class J fuse with a cylindrical body. It is rated for 40 A at 600 V AC and 300 V DC, identified by manufacturer part number A4J40.

SKU 3G-OTH-133118

Brand
MERSEN
Item
Fuse: A4J Series, Class J, Cylindrical Body, Fast-Acting, 40 A, 600 V AC
Category
Fast-Acting Cylindrical Fuses
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Technical Specifications

MERSEN
Manufacturer Part Number
A4J40
Type
Class J, Cylindrical Body, Fast-Acting, 40 A
AC
600 V
DC
300 V
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MERSEN Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MERSEN A4J Series is a fast-acting cylindrical fuse, specifically a Class J fuse with a cylindrical body. It is rated for 40 A at 600 V AC and 300 V DC, identified by manufacturer part number A4J40.

Frequently Asked Questions

What is the MERSEN A4J40 fuse used for?

The MERSEN A4J40 is a fast-acting Class J cylindrical fuse rated 40 A at 600 V AC and 300 V DC. It protects industrial equipment such as motor control centers, panelboards, and branch circuits from short circuits and overloads, ensuring reliable operation in manufacturing and process industries.

What are the specifications of the MERSEN A4J40 fuse?

The MERSEN A4J40 is a Class J, cylindrical-body, fast-acting fuse rated 40 A, 600 V AC, and 300 V DC. Its manufacturer part number is A4J40. This fuse provides high interrupting capacity for protecting electrical circuits in industrial environments where fast response to faults is critical.

Where to buy MERSEN A4J40 fuses worldwide?

3G Electric supplies the MERSEN A4J40 fuse worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time; we source and deliver this fuse to any country.

How to select the correct MERSEN A4J40 fuse for an application?

To select the MERSEN A4J40, verify your circuit's voltage (max 600 V AC or 300 V DC) and continuous current (40 A). Ensure the fuse is fast-acting for sensitive electronics or motor starters. Class J rejection-style holders prevent substitution with lower-rated fuses. Consult a qualified engineer for 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 cylindrical fuses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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