MERSEN FUSE A 120 URD 71 LLI 0500 A120URD71LLI0500

MERSEN FUSE A 120 URD 71 LLI 0500 A120URD71LLI0500

High-speed aR fuse rated at 500A, 1100VAC IEC and 1200VAC UL with striker indication and slotted blade terminals for industrial semiconductor protection.

SKU: M300667Alt SKU: A120URD71LLI0500MPN: M300667
Price
List Price £173.23 ex VAT
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Sold in packs of 3

£173.23

Why Choose the Mersen M300667 High Speed Semiconductor Fuse?

The Mersen M300667, catalogue number A120UD71LLI500, is a premium Protistor® square body high speed semiconductor fuse engineered to provide ultra-fast protection for modern power electronic equipment. Designed specifically for semiconductor applications, it protects IGBTs, thyristors, diodes and other sensitive power devices against damaging short circuit faults in demanding industrial environments.

With a 500 A current rating, 1100 V AC IEC / 1200 V AC UL voltage rating and an aR operating class, the M300667 delivers exceptional fault interruption performance while minimising let-through energy. Its robust square body construction and high breaking capacity make it an excellent choice for industrial power conversion equipment, motor drives and renewable energy systems.

The fuse features a Size 71 square body design with long slotted blade terminals and an integrated striker indicator, allowing easy installation into compatible fuse holders and remote monitoring systems used throughout industrial electrical installations.

Key Advantages

  • Ultra-fast aR semiconductor protection fuse.
  • 500 A rated current for demanding industrial applications.
  • 1100 V AC IEC / 1200 V AC UL voltage rating.
  • Protects IGBTs, thyristors, diodes and other semiconductor devices.
  • Low let-through energy helps minimise equipment damage.
  • Integrated striker for remote indication.
  • High 150 kA breaking capacity.

Key Features

  • Mersen Protistor® semiconductor fuse.
  • Manufacturer part number: M300667.
  • Catalogue number: A120UD71LLI500.
  • 500 A rated current.
  • 1100 V AC IEC / 1200 V AC UL.
  • aR operating class.
  • Size 71 square body construction.
  • Long slotted blade terminals.
  • Integrated striker indicator.
  • Silver-plated contact surfaces for reliable conductivity.

Reliable Protection for Industrial Power Electronics

High speed semiconductor fuses are designed to interrupt fault currents before they can damage expensive semiconductor devices. Their ultra-fast characteristics minimise thermal stress while improving system reliability and reducing costly equipment downtime.

The Mersen M300667 is widely specified for industrial automation, power converters, renewable energy equipment and motor control systems where dependable semiconductor protection is essential.

Typical Applications

  • Variable frequency drives (VFDs).
  • Industrial motor drives.
  • Power converters and rectifiers.
  • UPS systems.
  • Renewable energy inverters.
  • Industrial automation equipment.
  • OEM electrical control panels.

Technical Specifications

Item number M300667
Catalogue No A120UD71LLI500
Description Square Body High-Speed Fuse Protistor® Size 71 aR 1100VAC IEC 1200VAC UL 500A With Striker Slotted Blades long
EAN/UPC Code 3605340331868
Rated voltage AC UL 1200 V
Rated voltage AC IEC 1100 V
Ampere Rating 500 A
AC or DC AC
Speed/Characteristic aR
Fuse Size 71
Mounting Bolted
Clearing I2t At Rated Voltage 441 kA²s
Melting I2t 68 kA²s
AC Max I.R./Breaking Capacity I1: 150 kA
Indication System Yes
Indication System Type Striker
Connection/Terminal Material Silver-Plated Copper
Connection/Terminal Type Slotted Blades
Product Width 51 mm
Product Length 157.4 mm
Product Height 56.5 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 1.62 kg
Sell Pack Width 155 mm
Sell Pack Length 165 mm
Sell Pack Height 60 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.54 kg
Power Dissipation at Rated Current Value 100 W
Fuse Type Semiconductor
Fuse Class aR
Voltage 1100 V

Frequently Asked Questions

What is the Mersen M300667 used for?

The M300667 is an ultra-fast semiconductor fuse designed to protect IGBTs, thyristors, diodes and other semiconductor devices from damaging short circuit faults.

What is the current rating of this fuse?

The fuse has a 500 A rated current.

What voltage is the M300667 rated for?

The fuse is rated for 1100 V AC (IEC) and 1200 V AC (UL) applications.

What does the aR operating class mean?

The aR operating class provides ultra-fast short circuit protection specifically for semiconductor devices while overload protection is provided elsewhere within the electrical system.

Where is this fuse typically installed?

The M300667 is commonly installed in industrial drives, power converters, UPS systems, renewable energy equipment and OEM electrical panels.

Trusted for Industrial Semiconductor Protection

Mersen Protistor® semiconductor fuses are trusted worldwide by electrical engineers, OEM manufacturers and panel builders to provide dependable protection for critical industrial power electronic equipment.

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