SKU: H300824Alt SKU: 12,5URD71ESF0450MPN: H300824
MERSEN FUSE 12,5 URD 71 ESF 0450 12,5URD71ESF0450

MERSEN FUSE 12,5 URD 71 ESF 0450 12,5URD71ESF0450

Why Choose the MERSEN FUSE 12,5 URD 71 ESF 0450 12,5URD71ESF0450? MERSEN FUSE 12,5 URD 71 ESF 0450 12,5URD71ESF0450 delivers robust, standards-compliant performance for demanding electrical applications. This model provides reliable protection and ease of installation, with all key features engineered for maximum safety and efficiency. Key Takeaways – Product Name: MERSEN FUSE 12,5 URD 71 ESF 0450 12,5URD71ESF0450 – Key Specs: See description below Frequently Asked Questions – What is the primary application? – Is this product certified? – What are the installation options? – What are the key benefits? – Where can I find technical data? Speed & Safety Benefits – Reliable Performance: Engineered for consistent results – Safe Operation: Built to meet modern standards – Quick Installation: Designed for installer convenience Key Features of MERSEN FUSE 12,5 URD 71 ESF 0450 12,5URD71ESF0450 – See full description below – Engineered for reliability – Technical support available What is the primary application?+ See product description for detailed use cases. Is this product certified?+ Consult technical data or documentation for certifications. What are the installation options?+ Refer to the installation manual or contact our team for guidance. What are the key benefits?+ Engineered for performance, reliability, and ease of use. Where can I find technical data?+ Technical datasheets are available on request or on our website.

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Why Choose the Mersen H300824 Protistor® High-Speed Fuse?

The Mersen H300824 (Catalogue No. 12,5 URD 71 ESF 0450) is a Protistor® Size 71 aR square body high-speed semiconductor fuse designed to provide exceptional protection for power semiconductor devices in demanding industrial applications. This model is rated at 450A and 1250VAC, making it suitable for protecting converters, drives, UPS systems and other power electronic equipment.

Featuring a partial-range aR operating characteristic, the H300824 rapidly clears short-circuit faults while minimising thermal and mechanical stress on sensitive semiconductor components such as IGBTs, thyristors and diodes. It incorporates an integrated striker (ESF) indicator to simplify maintenance and remote indication.

Manufactured by Mersen, the H300824 forms part of the internationally recognised Protistor® range, offering dependable protection, excellent reliability and high interrupting performance for modern industrial power conversion systems.

Key Advantages

  • Genuine Mersen Protistor® semiconductor protection fuse.
  • Ultra-fast aR characteristic for semiconductor protection.
  • 450A continuous current rating.
  • 1250VAC operating voltage.
  • Integrated ESF striker indication.
  • High breaking capacity for industrial power electronics.
  • Designed to minimise semiconductor damage during fault conditions.
  • Suitable for demanding industrial environments.

Key Features

  • Manufacturer: Mersen
  • Series: Protistor® Size 71
  • Manufacturer Part Number: H300824
  • Catalogue Number: 12,5 URD 71 ESF 0450
  • Square body high-speed semiconductor fuse.
  • aR ultra-fast operating class.
  • Integrated ESF striker indicator.
  • Designed for semiconductor and converter protection.

Technical Specifications

  • Manufacturer: Mersen
  • Manufacturer Part Number: H300824
  • Catalogue Number: 12,5 URD 71 ESF 0450
  • Series: Protistor® Size 71
  • Fuse Type: Square Body High-Speed Semiconductor Fuse
  • Operating Class: aR
  • Rated Current: 450A
  • Rated Voltage: 1250VAC
  • Indicator: ESF Striker
  • Body Size: Size 71
  • Application: Semiconductor protection
  • Mounting: Square body bolted installation

Typical Applications

  • Variable speed drives.
  • Industrial inverters.
  • UPS systems.
  • Renewable energy converters.
  • Battery energy storage systems.
  • Motor control centres.
  • Industrial rectifiers.
  • Power conversion equipment.

Frequently Asked Questions

What is the Mersen H300824 used for?

The H300824 is a Protistor® high-speed semiconductor fuse designed to protect IGBTs, thyristors, diodes and other sensitive power semiconductor devices against short-circuit faults.

What is the current rating?

The Mersen H300824 has a continuous current rating of 450A.

What is the voltage rating?

This fuse is rated for operation at 1250VAC.

What does the aR characteristic mean?

The aR operating class provides partial-range ultra-fast short-circuit protection specifically for semiconductor devices and should always be used together with suitable overload protection.

Does this fuse include an indicator?

Yes. The H300824 incorporates an ESF striker indicator to provide visual or remote fuse operation indication.

Trusted by Industry

Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, panel builders and maintenance engineers for protecting critical power electronic equipment in industrial applications.

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