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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 250 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, 250 A, 600 V AC

The MERSEN A4BY Series Class L Time-Delay Bolt-On Fuse (MPN A4BY250) is a 250 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-27080

Brand
MERSEN
Item
Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 250 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
A4BY250
Series
A4BY
Type
A4BY Series, Bolt-On Body, Time-Delay, 250 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 A4BY250) is a 250 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 A4BY250 fuse used for?

The MERSEN A4BY250 is a Class L time-delay bolt-on fuse rated 250 A, 600 V AC, 300 V DC. It protects industrial equipment such as motors, transformers, and feeders from overcurrents while tolerating harmless inrush currents, reducing nuisance blowing.

What are the specifications of the MERSEN A4BY250 fuse?

The MERSEN A4BY250 is a 250 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 startup surges in heavy industrial circuits.

Where to buy MERSEN A4BY250 fuses worldwide?

You can source the MERSEN A4BY250 fuse through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring reliable supply for your operations.

How to select the correct MERSEN A4BY fuse for an application?

Select the MERSEN A4BY fuse based on system voltage (up to 600 V AC or 300 V DC), continuous current rating (250 A for the A4BY250), and available fault current. Ensure the bolt-on body matches your fuse holder and that time-delay characteristics suit motor or transformer starting loads.

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, 350 A, 600 V AC, 300 V DC (MPN A4BY350)
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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, 300 A, 600 V AC, 300 V DC (MPN A4BY300)
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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, 200 A, 600 V AC, 300 V DC (MPN A4BY200)
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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, 600 A, 600 V AC, 300 V DC (MPN A4BY600)
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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, 2.5 kA, 600 V AC, 300 V DC (MPN A4BY2500)
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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 2.5 kA, 600 V AC, 300 V DC (MPN A4BY2500)
MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 400 A, 600 V AC, 300 V DC (MPN A4BY400)
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MERSEN Fuse: Class L, A4BY Series, Bolt-On Body, Time-Delay, 400 A, 600 V AC, 300 V DC (MPN A4BY400)

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