MERSEN FUSE A 130 URD 71 LLI 0400 A130URD71LLI0400

MERSEN FUSE A 130 URD 71 LLI 0400 A130URD71LLI0400

Engineered for demanding industrial and power electronics applications, this Protistor® high-speed fuse delivers reliable circuit protection at 1250V AC (IEC) and 1300V AC (UL) with a robust 400A rating. The slotted long blades and integrated striker facilitate secure mounting and immediate fuse status indication.

SKU: K300665Alt SKU: A130URD71LLI0400MPN: K300665
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List Price £166.71 ex VAT
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Why Choose the Mersen K300665 High-Speed Semiconductor Fuse?

The Mersen K300665 is a premium Protistor® square body high-speed semiconductor fuse engineered to provide ultra-fast protection for sensitive power electronic devices. Designed for demanding industrial applications, it safeguards IGBTs, thyristors, diodes, inverters and power conversion equipment against damaging short circuits whilst minimising fault energy and equipment downtime.

Part of the renowned Mersen Protistor® Size 71 aR series, the K300665 is designed for modern industrial drive systems, renewable energy installations, UPS equipment and heavy-duty automation applications. Its ceramic square body construction, silver-plated slotted blade terminals and integrated striker indicator provide dependable long-term performance in demanding electrical environments.

With a 400 A current rating, 1250 V AC IEC / 1300 V AC UL voltage rating and 126 kA breaking capacity, the K300665 delivers exceptional semiconductor protection for high-power industrial equipment.

Key Advantages

  • Ultra-fast aR semiconductor protection fuse.
  • 400 A current rating for demanding industrial power applications.
  • 1250 V AC IEC / 1300 V AC UL voltage capability.
  • 126 kA breaking capacity for outstanding fault protection.
  • Integrated striker indicator enables rapid fault identification.
  • Silver-plated slotted blade terminals ensure excellent electrical conductivity.
  • Robust ceramic construction for reliable long-term service.

Key Features

  • Mersen Protistor® Size 71 aR series.
  • 400 A rated current.
  • 1250 V AC IEC / 1300 V AC UL rated voltage.
  • Ultra-fast aR operating characteristic.
  • 126 kA AC breaking capacity.
  • Integrated striker indication.
  • Slotted blade terminals with silver-plated contacts.
  • Square ceramic body construction.
  • Designed for semiconductor protection.

Reliable Protection for High-Power Electronics

High-speed semiconductor fuses are specifically designed to protect expensive power electronic devices by interrupting short-circuit currents before damaging thermal energy can reach sensitive semiconductor components. Their ultra-fast operation helps improve equipment reliability whilst reducing maintenance costs and production downtime.

The Mersen Protistor® range is trusted globally by machine builders, panel manufacturers and industrial engineers for protecting variable frequency drives, UPS systems, renewable energy converters and industrial power supplies.

Typical Applications

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

Technical Specifications

Item number K300665
Catalogue No A130UD71LLI400
Description Square Body High-Speed Fuse Protistor® Size 71 aR 1250VAC IEC 1300VAC UL 400A With Striker Slotted Blades long
EAN/UPC Code 3605340331844
Rated voltage AC UL 1300 V
Rated voltage AC IEC 1250 V
Ampere Rating 400 A
AC or DC AC
Speed/Characteristic aR
Fuse Size 71
Mounting Bolted
Clearing I2t At Rated Voltage 308 kA²s
Melting I2t 38 kA²s
AC Max I.R./Breaking Capacity I1: 126 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 80 W
Fuse Type Semiconductor
Fuse Class aR
Voltage 1250 V

Frequently Asked Questions

What is the Mersen K300665 used for?

The K300665 provides ultra-fast protection for semiconductors including IGBTs, thyristors, diodes and other sensitive power electronic devices.

What is the current rating of this fuse?

The Mersen K300665 has a 400 A rated current.

What voltage is the fuse rated for?

It is rated for 1250 V AC (IEC) and 1300 V AC (UL).

Does the K300665 include a fuse indicator?

Yes. It incorporates an integrated striker indicator to provide quick visual indication when the fuse has operated.

Where is the Mersen K300665 typically installed?

It is commonly installed in industrial drives, UPS systems, renewable energy converters, motor control equipment and semiconductor protection circuits.

Trusted for Critical Semiconductor Protection

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

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