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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 400 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, 400 A, 600 V AC

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY400) is a 400 A, 600 V AC, 300 V DC industrial fuse. This bolt-on body fuse offers time-delay characteristics for handling inrush currents.

SKU 3G-OTH-26712

Brand
MERSEN
Item
Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 400 A, 600 V AC
Category
Time-Delay Bolt-On Fuses
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Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

MERSEN
Manufacturer Part Number
A4BY400
Series
A4BY
Type
A4BY Series, Bolt-On Body, Time-Delay, 400 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 A4BY400) is a 400 A, 600 V AC, 300 V DC industrial fuse. This bolt-on body fuse offers time-delay characteristics for handling inrush currents.

Frequently Asked Questions

What is the MERSEN A4BY400 fuse used for?

The MERSEN A4BY400 is a Class L time-delay bolt-on fuse rated 400 A, 600 V AC, 300 V DC. It protects industrial circuits and equipment from overcurrents while tolerating harmless inrush currents, making it suitable for motor starters, transformers, and other inductive loads.

What are the specifications of the MERSEN A4BY400 fuse?

The MERSEN A4BY400 is a 400 A, 600 V AC, 300 V DC Class L time-delay bolt-on fuse from the A4BY series. It features a bolt-on body design for secure mounting and time-delay characteristics to handle inrush currents without nuisance opening.

Where to buy MERSEN A4BY400 fuse worldwide?

3G Electric supplies the MERSEN A4BY400 fuse worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this MERSEN A4BY series fuse.

How to select the correct MERSEN A4BY400 fuse for an application?

Select the MERSEN A4BY400 fuse by matching its 400 A rating, 600 V AC / 300 V DC voltage, and Class L time-delay characteristics to your circuit's continuous current and inrush requirements. Ensure the bolt-on body fits your fuse holder and that the interrupting rating meets system fault levels.

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, 300 A, 600 V AC, 300 V DC (MPN A4BY300)
MERSEN
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 300 A, 600 V AC, 300 V DC (MPN A4BY300)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 600 A, 600 V AC, 300 V DC (MPN A4BY600)
MERSEN
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 600 A, 600 V AC, 300 V DC (MPN A4BY600)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 200 A, 600 V AC, 300 V DC (MPN A4BY200)
MERSEN
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 200 A, 600 V AC, 300 V DC (MPN A4BY200)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 250 A, 600 V AC, 300 V DC (MPN A4BY250)
MERSEN
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 250 A, 600 V AC, 300 V DC (MPN A4BY250)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 350 A, 600 V AC, 300 V DC (MPN A4BY350)
MERSEN
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 350 A, 600 V AC, 300 V DC (MPN A4BY350)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 500 A, 600 V AC, 300 V DC (MPN A4BY500)
MERSEN
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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