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MERSEN Fuse: Class L, A4BQ 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, A4BQ Series, Bolt-On Body, Time-Delay, 400 A, 600 V AC

The MERSEN A4BQ Series Class L Time-Delay Bolt-On Fuse (MPN A4BQ400) is a 400 A, 600 V AC, 500 V DC industrial fuse with a bolt-on body. It provides time-delay overload protection for high-current circuits.

SKU 3G-OTH-27718

Brand
MERSEN
Item
Fuse: Class L, A4BQ Series, Bolt-On Body, Time-Delay, 400 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
A4BQ400
Series
A4BQ
Type
A4BQ Series, Bolt-On Body, Time-Delay, 400 A
AC
600 V
DC
500 V

Technical Documents

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

Product Description

The MERSEN A4BQ Series Class L Time-Delay Bolt-On Fuse (MPN A4BQ400) is a 400 A, 600 V AC, 500 V DC industrial fuse with a bolt-on body. It provides time-delay overload protection for high-current circuits.

Frequently Asked Questions

What is the MERSEN A4BQ400 fuse used for?

The MERSEN A4BQ400 is a Class L time-delay bolt-on fuse rated 400 A, 600 V AC, and 500 V DC. It protects high-current industrial circuits, such as motor feeders, transformers, and main disconnects, by allowing temporary overloads without nuisance opening.

What are the specifications of the MERSEN A4BQ400 fuse?

The MERSEN A4BQ400 is a Class L, A4BQ Series, bolt-on body, time-delay fuse rated 400 A, 600 V AC, and 500 V DC. Its bolt-on design ensures secure mounting in high-current applications. The manufacturer part number is A4BQ400.

Where to buy the MERSEN A4BQ400 fuse worldwide?

You can source the MERSEN A4BQ400 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.

How to select the correct MERSEN A4BQ400 fuse for an application?

Select the MERSEN A4BQ400 fuse by matching its 400 A rating, 600 V AC or 500 V DC voltage, and Class L time-delay characteristics to your circuit's full-load current and inrush requirements. Ensure the bolt-on body fits your existing fuse holder or disconnect switch.

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, A4BQ Series, Bolt-On Body, Time-Delay, 500 A, 600 V AC, 500 V DC (MPN A4BQ500)
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MERSEN Fuse: Class L, A4BQ Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC, 500 V DC (MPN A4BQ4000)
MERSEN Fuse: Class L, A4BQ Series, Bolt-On Body, Time-Delay, 700 A, 600 V AC, 500 V DC (MPN A4BQ700)
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MERSEN Fuse: Class L, A4BQ Series, Bolt-On Body, Time-Delay, 700 A, 600 V AC, 500 V DC (MPN A4BQ700)

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