MERSEN FUSE A070 URD 33 TTI 0500 A070URD33TTI0500

MERSEN FUSE A070 URD 33 TTI 0500 A070URD33TTI0500

Fast-acting Protistor® Size 33 aR fuse rated at 500A for reliable protection of power semiconductors with striker indication and flush ends UNC threads.

SKU: X300446Alt SKU: A070UD33TTI500MPN: X300446
Price
List Price £169.05 ex VAT
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£169.05
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Sold in packs of 3

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Why Choose the Mersen X300446 Protistor® High-Speed Fuse?

The Mersen X300446 is an industrial high-speed semiconductor protection fuse designed to protect sensitive power electronic components from damaging short-circuit currents. Manufactured as part of Mersen’s established Protistor® fuse range, it is intended for electrical systems that require rapid fault interruption and controlled energy let-through.

High-speed fuses such as the X300446 help protect IGBTs, thyristors, diodes and rectifier assemblies by interrupting fault currents before excessive thermal energy can damage the semiconductor components. This makes the fuse suitable for maintaining industrial drives, converters, inverters and other critical power electronic equipment.

The Mersen X300446 provides a dependable replacement option for industrial maintenance, repair and equipment refurbishment. Before installation, its current rating, voltage rating, operating class, terminal configuration and physical dimensions should be checked against the original fuse label or the equipment manufacturer’s documentation.

Key Advantages

  • High-speed semiconductor protection fuse for industrial equipment.
  • Rapid fault interruption helps protect sensitive electronic components.
  • Low energy let-through helps reduce thermal and electrical damage.
  • Suitable for maintenance and refurbishment of power conversion equipment.
  • Industrial construction supports reliable operation in demanding environments.
  • Manufactured by Mersen, a specialist in electrical protection technology.

Key Features

  • Mersen Protistor® high-speed fuse technology.
  • Designed for semiconductor short-circuit protection.
  • Suitable for protecting IGBTs, thyristors and power diodes.
  • Fast operating response for reduced fault energy.
  • Industrial-duty fuse construction.
  • Suitable for compatible fuse holders or bolted mounting systems.
  • Replacement component for industrial electrical equipment.
  • Designed for power conversion and motor control applications.

Reliable Protection for Power Semiconductor Equipment

Power semiconductor devices can be permanently damaged by short-circuit currents within a very short period. High-speed fuses are engineered to interrupt these currents rapidly, limiting the electrical energy that passes through the protected circuit and helping prevent extensive damage to valuable equipment.

Mersen Protistor® fuses are used in industrial power electronic systems where rapid operation and dependable short-circuit protection are essential. Correct fuse selection is critical, so the replacement device must match the original fuse’s electrical ratings, operating characteristics, dimensions and connection arrangement.

Typical Applications

  • Variable frequency drives and motor control equipment.
  • Industrial power converters and rectifiers.
  • Uninterruptible power supply systems.
  • Renewable energy converters and inverters.
  • Industrial automation and production machinery.
  • Semiconductor-based power distribution equipment.

Technical Specifications

Item number X300446
Catalogue No A070UD33TTI500
Description Square Body High-Speed Fuse Protistor® Size 33 aR 690VAC IEC 700VAC UL 500A With Striker Flush ends UNC threads
EAN/UPC Code 3605340328516
Rated voltage AC UL 700 V
Rated voltage AC IEC 690 V
Ampere Rating 500 A
RoHS Compliant Yes
AC or DC AC
Speed/Characteristic aR
Fuse Size 33
Mounting Bolted
Clearing I2t At Rated Voltage 110 kA²s
Melting I2t 19 kA²s
AC Max I.R./Breaking Capacity I1: 200 kA
Design Details Standard Terminal
Indication System Yes
Indication System Type Striker
Connection/Terminal Material Silver-Plated Brass
Connection/Terminal Type Flush ends
Product Width 73 mm
Product Length 50.6 mm
Product Height 78.5 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 2.682 kg
Sell Pack Width 86 mm
Sell Pack Length 247 mm
Sell Pack Height 94 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.894 kg
Power Dissipation at Rated Current Value 105 W
HS Code 85361090
Fuse Type Semiconductor
Fuse Class aR
Voltage 690 V

Frequently Asked Questions

What is the Mersen X300446 used for?

The Mersen X300446 is used to provide high-speed short-circuit protection for semiconductor components installed in industrial power electronic equipment.

Which components can the X300446 protect?

It is intended for the protection of sensitive devices such as IGBTs, thyristors, power diodes and rectifier assemblies.

Can the Mersen X300446 replace a general-purpose fuse?

A high-speed semiconductor fuse has different operating characteristics from a general-purpose fuse. It should only be installed where its ratings, fuse class, dimensions and terminal arrangement match the equipment requirements.

Where is the X300446 typically installed?

It may be installed in industrial drives, converters, rectifiers, inverters, UPS systems and other semiconductor-based power equipment.

What should be checked before installing the X300446?

Confirm the current rating, voltage rating, utilisation category, breaking capacity, terminal configuration and physical dimensions against the original fuse or equipment documentation.

Trusted Protection for Industrial Power Electronics

Mersen semiconductor protection fuses are used in industrial electrical systems to provide rapid fault clearance and dependable protection for sensitive power electronic components.

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