MERSEN FUSE 4 URD 33 TTF 1250 PC33UD40V1250TF

MERSEN FUSE 4 URD 33 TTF 1250 PC33UD40V1250TF

Why Choose the MERSEN FUSE 4 URD 33 TTF 1250 PC33UD40V1250TF?

SKU: K301355Alt SKU: PC33UD40V1250TFMPN: K301355
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Why Choose the Mersen K301355 High-Speed Semiconductor Fuse?

The Mersen K301355 is a high-performance Protistor® square body semiconductor protection fuse designed to deliver ultra-fast protection for high-power semiconductor devices operating in demanding industrial applications. Engineered for the protection of IGBTs, thyristors, diodes, rectifiers, inverters and power conversion systems, this fuse rapidly interrupts fault currents to minimise equipment damage and reduce downtime.

Part of the trusted Mersen Protistor® Size 33 aR series, the K301355 combines robust ceramic construction with threaded terminals and an integrated striker indicator for dependable operation in industrial automation, motor drives, renewable energy systems and heavy-duty power electronics.

With a 1250 A current rating, 400 V AC rated voltage and aR operating characteristic, the K301355 provides reliable short-circuit protection specifically for semiconductor equipment where rapid fault clearance is essential.

Key Advantages

  • Ultra-fast aR semiconductor protection fuse.
  • 1250 A rated current for high-power industrial applications.
  • 400 V AC rated voltage.
  • Designed specifically to protect sensitive semiconductor devices.
  • Integrated striker indicator for quick fuse status identification.
  • Threaded terminals provide secure electrical connections.
  • Robust square ceramic body for long service life.

Key Features

  • Mersen Protistor® Size 33 aR series.
  • 1250 A rated current.
  • 400 V AC rated voltage.
  • Ultra-fast aR operating characteristic.
  • Square ceramic body construction.
  • Integrated striker indication.
  • Threaded terminal connections.
  • Designed for industrial semiconductor protection.

Reliable Protection for Industrial Power Electronics

High-speed semiconductor fuses are engineered to interrupt high fault currents before excessive thermal energy reaches sensitive semiconductor devices. Their extremely fast operating characteristics help extend equipment life, improve reliability and reduce maintenance costs.

The Mersen Protistor® range is widely specified by machine builders, OEM manufacturers and industrial engineers for protecting variable frequency drives, industrial converters, UPS systems and renewable energy installations where dependable semiconductor protection is essential.

Typical Applications

  • Variable frequency drives (VFDs).
  • Industrial inverters and converters.
  • Protection of IGBT and thyristor modules.
  • UPS systems.
  • Renewable energy power conversion equipment.
  • Industrial automation systems.
  • High-power semiconductor protection circuits.

Technical Specifications

Manufacturer Mersen
Series Protistor® Size 33
Model K301355
Catalogue number PC33UD40V1250TF
Product type High-speed semiconductor protection fuse
Rated current 1250 A
Rated voltage 400 V AC
Operating characteristic aR
Construction Square body
Indicator Centre striker
Terminal type Threaded terminals
Body material Ceramic
Application Semiconductor protection
Mounting Bolted installation
Device Type Fuse link
Fuse Type Semiconductor
Fuse Class aR
Current 1250 A
Voltage 400 V

Frequently Asked Questions

What is the Mersen K301355 used for?

The K301355 is designed to provide ultra-fast protection for sensitive semiconductor devices including IGBTs, thyristors, diodes and industrial power converters.

What is the current rating of this fuse?

The Mersen K301355 has a 1250 A current rating.

What voltage is the fuse rated for?

It is rated for 400 V AC operation.

Does the K301355 include a fuse indicator?

Yes. The fuse incorporates an integrated centre striker indicator to provide rapid identification after operation.

Where is the Mersen K301355 typically installed?

It is commonly installed in industrial drives, converters, UPS systems, renewable energy equipment and other semiconductor protection applications.

Trusted for Critical Semiconductor Protection

Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, panel builders and industrial engineers to provide dependable protection for high-value power electronic equipment operating in demanding industrial environments.

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