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MERSEN Semiconductor Fuse: A70QS Series, Fast-Acting, 50 A, 700 V AC - Fast-Acting Bolt-On Fuses
MERSENFast-Acting Bolt-On Fuses

MERSEN Semiconductor Fuse: A70QS Series, Fast-Acting, 50 A, 700 V AC

The MERSEN A70QS Series Semiconductor Fuse (MPN A70QS50-4) is a fast-acting bolt-on fuse rated at 50 A and 700 V AC/700 V DC. This AC/DC voltage-type fuse is designed for semiconductor protection applications.

SKU 3G-OTH-25162

Also listed as: A70QS504 · A70QS50 4

Brand
MERSEN
Item
Semiconductor Fuse: A70QS Series, Fast-Acting, 50 A, 700 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
A70QS50-4
Series
A70QS
Type
Fast-Acting, 50 A
AC
700 V
Voltage Type
AC/DC
DC DC Volt Rating
700 V

Technical Documents

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

Product Description

The MERSEN A70QS Series Semiconductor Fuse (MPN A70QS50-4) is a fast-acting bolt-on fuse rated at 50 A and 700 V AC/700 V DC. This AC/DC voltage-type fuse is designed for semiconductor protection applications.

Frequently Asked Questions

What is the MERSEN A70QS50-4 semiconductor fuse used for?

The MERSEN A70QS50-4 is a fast-acting bolt-on fuse designed to protect semiconductor devices such as diodes, thyristors, and IGBTs from overcurrent faults. It is commonly used in power supplies, drives, and industrial equipment requiring reliable AC/DC protection at 700 V.

What are the specifications of the MERSEN A70QS50-4 fuse?

The MERSEN A70QS50-4 is a 50 A, fast-acting semiconductor fuse from the A70QS series. It has an AC voltage rating of 700 V and a DC voltage rating of 700 V. The fuse features a bolt-on mounting style and is designed for high-speed overcurrent protection in AC/DC circuits.

Where to buy the MERSEN A70QS50-4 fuse worldwide?

You can source the MERSEN A70QS50-4 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 on this fast-acting semiconductor fuse.

How to select the correct MERSEN A70QS series fuse for an application?

To select the correct MERSEN A70QS fuse, match the continuous current rating (e.g., 50 A) to your circuit load and ensure the voltage rating (700 V AC/700 V DC) exceeds your system voltage. Consider the fuse's fast-acting characteristic for semiconductor protection and verify bolt-on dimensions fit your holder.

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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