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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4,001 A, 600 V AC - Time-Delay Bolt-On Fuses
MERSENTime-Delay Bolt-On Fuses

MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4,001 A, 600 V AC

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY4001) is a 4,001 A, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in high-amperage…

SKU 3G-OTH-27343

Brand
MERSEN
Item
Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4,001 A, 600 V AC
Category
Time-Delay 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
A4BY4001
Series
A4BY
Type
A4BY Series, Bolt-On Body, Time-Delay, 4,001 A
AC
600 V
DC
300 V

Technical Documents

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

Product Description

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY4001) is a 4,001 A, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in high-amperage circuits.

Frequently Asked Questions

What is the MERSEN A4BY4001 fuse used for?

The MERSEN A4BY4001 is a Class L time-delay bolt-on fuse rated 4,001 A, 600 V AC, 300 V DC. It provides overcurrent protection in high-amperage industrial circuits, such as switchboards, panelboards, and motor control centers, where sustained overloads and short circuits must be safely interrupted.

What are the specifications of the MERSEN A4BY4001 fuse?

The MERSEN A4BY4001 is a Class L, A4BY Series time-delay bolt-on fuse. Key specs: 4,001 A, 600 V AC, 300 V DC. It features a bolt-on body for secure mounting in high-amperage applications. The time-delay characteristic allows temporary inrush currents without nuisance opening.

Where to buy the MERSEN A4BY4001 fuse worldwide?

3G Electric supplies the MERSEN A4BY4001 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 A4BY4001 fuse for an application?

To select the MERSEN A4BY4001, verify your circuit's continuous current rating (4,001 A maximum), voltage (600 V AC or 300 V DC), and available fault current. Ensure the bolt-on mounting matches your fuse holder. The time-delay feature suits circuits with motor or transformer inrush. Consult a licensed engineer for coordination.

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 time-delay 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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Compatible alternatives & equivalents

Cross-referenced by specification & description
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 500 A, 600 V AC, 300 V DC (MPN A4BY500)
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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 500 A, 600 V AC, 300 V DC (MPN A4BY500)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 1.8 kA, 600 V AC, 300 V DC (MPN A4BY1800)
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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 1 kA, 600 V AC, 300 V DC (MPN A4BY1000)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4.5 kA, 600 V AC, 300 V DC (MPN A4BY4500)
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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4.5 kA, 600 V AC, 300 V DC (MPN A4BY4500)

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