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MERSEN Fuse: Class L, A4BQ 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, A4BQ Series, Bolt-On Body, Time-Delay, 900 A, 600 V AC

The MERSEN A4BQ Series Class L Time-Delay Bolt-On Fuse (MPN A4BQ900) is a 900 A, 600 V AC, 500 V DC industrial fuse. It features a bolt-on body and time-delay operation for overcurrent protection.

SKU 3G-OTH-27669

Brand
MERSEN
Item
Fuse: Class L, A4BQ Series, Bolt-On Body, Time-Delay, 900 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
A4BQ900
Series
A4BQ
Type
A4BQ Series, Bolt-On Body, Time-Delay, 900 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 A4BQ900) is a 900 A, 600 V AC, 500 V DC industrial fuse. It features a bolt-on body and time-delay operation for overcurrent protection.

Frequently Asked Questions

What is the MERSEN A4BQ900 fuse used for?

The MERSEN A4BQ900 is a 900 A, 600 V AC, 500 V DC Class L time-delay bolt-on fuse used for overcurrent protection in industrial power distribution, motor circuits, and feeder applications. Its time-delay characteristic allows it to withstand temporary inrush currents without nuisance opening.

What are the specifications of the MERSEN A4BQ900 fuse?

The MERSEN A4BQ900 is a Class L, A4BQ Series, bolt-on body, time-delay fuse rated 900 A, 600 V AC, and 500 V DC. The manufacturer part number is A4BQ900. It provides reliable overcurrent protection in high-current industrial circuits.

Where to buy MERSEN A4BQ900 fuses worldwide?

3G Electric supplies the MERSEN A4BQ900 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 on this Class L time-delay bolt-on fuse.

How to select the right MERSEN A4BQ900 fuse for an application?

To select the MERSEN A4BQ900, verify your system voltage does not exceed 600 V AC or 500 V DC, and the continuous load current is at or below 900 A. The time-delay feature suits motor or transformer circuits with high inrush. Always consult the manufacturer's data sheet for coordination and interrupting rating.

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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