MERSEN FUSE A 070 URD 31 TTI 0450 A070URD31TTI0450

MERSEN FUSE A 070 URD 31 TTI 0450 A070URD31TTI0450

High-speed fuse with striker indication, rated at 450A for 690VAC IEC and 700VAC UL applications, featuring a robust ceramic square body and flush end terminals with UNC threads.

SKU: F300477Alt SKU: A070UD31TTI450MPN: F300477
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List Price £147.04 ex VAT
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Why Choose the Mersen F300477 Protistor® High-Speed Fuse?

The Mersen F300477 is an industrial Protistor® high-speed semiconductor protection fuse designed to protect sensitive power electronic equipment against damaging short-circuit currents. Manufactured by Mersen, it is intended for installations where rapid fault interruption and low let-through energy are essential for protecting valuable semiconductor components.

This high-speed fuse is suitable for use with equipment incorporating IGBTs, thyristors, rectifiers, diodes and power semiconductor modules. Its robust industrial construction supports dependable operation in demanding power conversion, motor control and automation applications.

The Mersen F300477 provides an effective protection solution for variable frequency drives, industrial converters, inverters, uninterruptible power supplies and other high-power electronic systems. Its fast operating characteristics help minimise thermal and electrical stress while reducing the risk of costly equipment damage and unplanned downtime.

Key Advantages

  • High-speed semiconductor protection fuse for industrial power electronics.
  • Rapid short-circuit interruption helps protect sensitive components.
  • Low let-through energy reduces electrical and thermal stress.
  • Suitable for protecting IGBTs, thyristors, diodes and rectifier assemblies.
  • Robust construction for demanding industrial environments.
  • Supports reliable operation of drives, converters and inverter systems.
  • Manufactured by Mersen, a specialist in electrical protection solutions.

Key Features

  • Mersen Protistor® high-speed fuse technology.
  • Designed specifically for semiconductor protection.
  • Fast-acting response to high short-circuit currents.
  • Low I²t performance for enhanced component protection.
  • Industrial fuse construction for reliable performance.
  • Suitable for power conversion and motor control equipment.
  • Compatible with correctly rated fuse holders and mounting systems.
  • Suitable for OEM, maintenance and replacement applications.

Reliable Protection for Power Semiconductor Equipment

Power semiconductor devices can be damaged within milliseconds when exposed to excessive fault current. High-speed fuses such as the Mersen F300477 are engineered to respond considerably faster than conventional general-purpose fuses, limiting the amount of damaging energy that passes through the protected circuit.

By interrupting severe short-circuit currents rapidly, the F300477 helps protect critical components and improve the overall reliability of industrial electrical equipment. Correct fuse selection must always consider the equipment voltage, operating current, prospective fault current and coordination requirements.

Typical Applications

  • Variable frequency drives and motor control systems.
  • Industrial power converters and rectifiers.
  • AC and DC inverter systems.
  • Uninterruptible power supplies.
  • Soft starters and industrial motor drives.
  • Renewable energy power conversion equipment.
  • Industrial automation and production machinery.
  • Protection of IGBT, thyristor and diode modules.

Technical Specifications

Item number F300477
Catalogue No A070UD31TTI450
Description Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 450A With Striker Flush ends UNC threads
EAN/UPC Code 3605340329063
Rated voltage AC UL 700 V
Rated voltage AC IEC 690 V
Ampere Rating 450 A
RoHS Compliant Yes
AC or DC AC
Speed/Characteristic aR
Fuse Size 31
Mounting Bolted
Clearing I2t At Rated Voltage 155000 A²s
Melting I2t 26500 A²s
AC Max I.R./Breaking Capacity I1: 200 kA
Indication System Yes
Indication System Type Striker
Connection/Terminal Material Silver-Plated Brass
Connection/Terminal Type Flush ends
Product Width 51 mm
Product Length 50.6 mm
Product Height 56.5 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 1.155 kg
Sell Pack Width 85 mm
Sell Pack Length 168 mm
Sell Pack Height 65 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.385 kg
Power Dissipation at Rated Current Value 70 W
HS Code 85361090
Country of Manufacture France
Fuse Type Semiconductor
Fuse Class aR
Voltage 690 V

Frequently Asked Questions

What is the Mersen F300477 used for?

The Mersen F300477 is used to protect sensitive semiconductor devices and industrial power electronic equipment against damaging short-circuit currents.

Which components can the F300477 protect?

It is designed for applications incorporating components such as IGBTs, thyristors, diodes, rectifiers and power semiconductor modules.

Is the F300477 a general-purpose fuse?

No. It is a specialised high-speed fuse intended primarily for semiconductor and power electronic protection rather than general cable overload protection.

Where is this fuse commonly installed?

It is commonly used in variable frequency drives, power converters, inverters, UPS systems, soft starters and other industrial electronic equipment.

What should be checked before replacing this fuse?

The manufacturer reference, current rating, voltage rating, fuse characteristic, dimensions, terminal arrangement and equipment requirements should all be verified before installation.

Trusted Semiconductor Protection from Mersen

Mersen Protistor® high-speed fuses are used by electrical engineers, machine builders and industrial maintenance professionals to protect valuable semiconductor equipment and support reliable operation in demanding power electronic systems.

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