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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 900 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, 900 A, 600 V AC

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY900) is a 900 A, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in electrical…

SKU 3G-OTH-27699

Brand
MERSEN
Item
Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 900 A, 600 V AC
Category
Time-Delay Bolt-On Fuses
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Technical Specifications

MERSEN
Manufacturer Part Number
A4BY900
Series
A4BY
Type
A4BY Series, Bolt-On Body, Time-Delay, 900 A
AC
600 V
DC
300 V

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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 A4BY900) is a 900 A, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in electrical distribution systems.

Frequently Asked Questions

What is the MERSEN A4BY900 fuse used for?

The MERSEN A4BY900 is a 900 A, 600 V AC, 300 V DC Class L time-delay bolt-on fuse used for overcurrent protection in industrial electrical distribution systems. It is designed to handle high-current circuits and provide reliable protection against short circuits and overloads in switchboards, panelboards, and motor control centers.

What are the specifications of the MERSEN A4BY900 fuse?

The MERSEN A4BY900 is a Class L time-delay bolt-on fuse rated at 900 A, 600 V AC, and 300 V DC. It is part of the A4BY Series and has a bolt-on body for secure mounting. The manufacturer part number is A4BY900. This fuse provides overcurrent protection in high-power electrical systems.

Where to buy the MERSEN A4BY900 fuse worldwide?

You can source the MERSEN A4BY900 fuse through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time. 3G Electric supplies genuine MERSEN fuses for industrial applications.

How to select the correct MERSEN A4BY900 fuse for an application?

To select the MERSEN A4BY900 fuse, verify that your circuit voltage does not exceed 600 V AC or 300 V DC and that the continuous load current is below 900 A. Ensure the bolt-on mounting matches your fuse holder. For time-delay applications, confirm that inrush currents are within the fuse's time-current curve. 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 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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Cross-referenced by specification & description
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 700 A, 600 V AC, 300 V DC (MPN A4BY700)
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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC, 300 V DC (MPN A4BY4000)

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