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MERSEN Semiconductor Fuse: A70QS Series, Fast-Acting, 125 A, 700 V AC - Fast-Acting Bolt-On Fuses
MERSENFast-Acting Bolt-On Fuses

MERSEN Semiconductor Fuse: A70QS Series, Fast-Acting, 125 A, 700 V AC

The MERSEN A70QS Series Semiconductor Fuse (MPN A70QS125-4K) is a fast-acting bolt-on fuse rated at 125 A and 700 V AC/700 V DC. This AC/DC voltage type fuse is designed for semiconductor protection in industrial…

SKU 3G-OTH-25724

Also listed as: A70QS1254K · A70QS125 4K

Brand
MERSEN
Item
Semiconductor Fuse: A70QS Series, Fast-Acting, 125 A, 700 V AC
Category
Fast-Acting Bolt-On Fuses
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

MERSEN
Manufacturer Part Number
A70QS125-4K
Series
A70QS
Type
Fast-Acting, 125 A
AC
700 V
Voltage Type
AC/DC
DC DC Volt Rating
700 V

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

Product Description

The MERSEN A70QS Series Semiconductor Fuse (MPN A70QS125-4K) is a fast-acting bolt-on fuse rated at 125 A and 700 V AC/700 V DC. This AC/DC voltage type fuse is designed for semiconductor protection in industrial equipment.

Frequently Asked Questions

What is the MERSEN A70QS125-4K semiconductor fuse used for?

The MERSEN A70QS125-4K is a fast-acting bolt-on fuse rated at 125 A and 700 V AC/700 V DC. It protects semiconductor devices like diodes and thyristors in industrial drives, power supplies, and converters from overcurrent faults.

What are the specifications of the MERSEN A70QS125-4K fuse?

The MERSEN A70QS125-4K is a fast-acting, 125 A fuse from the A70QS series. It has a voltage rating of 700 V AC and 700 V DC, making it suitable for AC/DC circuits. The bolt-on design ensures secure mounting in industrial equipment.

Where to buy the MERSEN A70QS125-4K fuse worldwide?

3G Electric supplies the MERSEN A70QS125-4K semiconductor fuse worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time.

How to select the right MERSEN A70QS series fuse for my application?

To select the correct MERSEN A70QS fuse, match the voltage rating (700 V AC/DC) and current rating (125 A for this model) to your circuit. Ensure the fast-acting characteristic aligns with your semiconductor's surge withstand. Consult the manufacturer's data sheet for I²t values.

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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