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MERSEN Semiconductor Fuse: A30QS Series, Fast-Acting, 40 A, 300 V AC - Fast-Acting Bolt-On Fuses
MERSENFast-Acting Bolt-On Fuses

MERSEN Semiconductor Fuse: A30QS Series, Fast-Acting, 40 A, 300 V AC

The MERSEN A30QS Series Semiconductor Fuse (MPN A30QS40-4) is a fast-acting bolt-on fuse rated at 40 A and 300 V AC/300 V DC. This A30QS series fuse is designed for AC/DC voltage applications.

SKU 3G-OTH-26882

Also listed as: A30QS404 · A30QS40 4

Brand
MERSEN
Item
Semiconductor Fuse: A30QS Series, Fast-Acting, 40 A, 300 V AC
Category
Fast-Acting 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
A30QS40-4
Series
A30QS
Type
Fast-Acting, 40 A
AC
300 V
Voltage Type
AC/DC
DC DC Volt Rating
300 V

Technical Documents

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

Product Description

The MERSEN A30QS Series Semiconductor Fuse (MPN A30QS40-4) is a fast-acting bolt-on fuse rated at 40 A and 300 V AC/300 V DC. This A30QS series fuse is designed for AC/DC voltage applications.

Frequently Asked Questions

What is the MERSEN A30QS40-4 semiconductor fuse used for?

The MERSEN A30QS40-4 is a fast-acting bolt-on fuse used to protect power semiconductors, such as diodes and thyristors, in AC/DC circuits up to 300 V. It is commonly applied in variable frequency drives, power supplies, and industrial rectifiers where rapid overcurrent interruption is critical to prevent component damage.

What are the specifications of the MERSEN A30QS40-4 fuse?

The MERSEN A30QS40-4 is a 40 A, fast-acting bolt-on fuse from the A30QS series. It is rated for 300 V AC and 300 V DC, making it suitable for mixed AC/DC voltage applications. The manufacturer part number is A30QS40-4, and it is designed for reliable overcurrent protection in semiconductor circuits.

Where to buy the MERSEN A30QS40-4 fuse worldwide?

You can source the MERSEN A30QS40-4 fuse worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time; we provide competitive pricing and reliable supply for this MERSEN semiconductor fuse.

How to select the correct MERSEN A30QS series fuse for my application?

To select the correct MERSEN A30QS series fuse, match the voltage rating (300 V AC/DC) and current rating (e.g., 40 A for the A30QS40-4) to your circuit requirements. Ensure the fast-acting characteristic aligns with the inrush current of your semiconductor load. Consult the fuse's I²t value and mounting style (bolt-on) for proper coordination.

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 fast-acting 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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