MERSEN FUSE A 070 URD 31 KI 0400 A070URD31KI0400

MERSEN FUSE A 070 URD 31 KI 0400 A070URD31KI0400

High-speed fuse designed for semiconductor protection with 400A rating, 690VAC IEC and 700VAC UL rated voltage, featuring striker indication and slotted blade terminals.

SKU: W300031Alt SKU: A070UD31KI400MPN: W300031
Price
List Price £149.54 ex VAT
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Sold in packs of 3

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Why Choose the Mersen W300031 Protistor® Fuse?

The Mersen W300031 is a high-performance Protistor® ultra-fast semiconductor fuse designed to provide superior protection for modern power electronic equipment. Engineered for demanding industrial applications, this square body fuse delivers rapid fault interruption to protect sensitive semiconductor components including IGBTs, thyristors, diodes and rectifiers from damaging short-circuit currents.

Manufactured by Mersen, a global specialist in electrical power and advanced materials, the W300031 combines excellent current limiting performance with high breaking capacity to minimise equipment damage and improve system reliability. Its robust construction and silver-plated contacts ensure dependable performance in harsh industrial environments.

With a 400 A current rating, 690 V AC IEC / 700 V AC UL voltage rating and an aR ultra-fast protection characteristic, the W300031 is ideally suited for protecting variable speed drives, industrial inverters, UPS systems, converters and renewable energy equipment.

Key Advantages

  • Ultra-fast Protistor® semiconductor protection fuse.
  • 400 A current rating for demanding industrial applications.
  • 690 V AC IEC / 700 V AC UL rated voltage.
  • aR characteristic designed specifically for semiconductor protection.
  • High interrupting capacity reduces equipment damage during faults.
  • Excellent current limiting performance.
  • Suitable for industrial drives, converters and power electronic systems.

Key Features

  • Manufacturer: Mersen
  • Series: Protistor® Size 31
  • Model: W300031 (A070UD31KI400)
  • Square body high-speed fuse.
  • 400 A rated current.
  • 690 V AC IEC / 700 V AC UL rating.
  • aR ultra-fast semiconductor protection.
  • Striker indicator.
  • Slotted blade terminals.
  • Silver-plated contact surfaces.
  • Suitable for protecting diodes, thyristors and IGBT devices.

Reliable Protection for Industrial Power Electronics

Ultra-fast semiconductor fuses are engineered to disconnect fault currents before excessive thermal energy can damage expensive power electronic components. Their rapid operating characteristics help maximise equipment availability while reducing maintenance costs and minimising production downtime.

The Mersen Protistor® range is trusted worldwide for protecting industrial motor drives, renewable energy systems, converters and UPS installations where dependable semiconductor protection is essential for safe and efficient operation.

Typical Applications

  • Variable frequency drives (VFDs).
  • Industrial motor drives.
  • Power converters.
  • UPS systems.
  • Renewable energy inverters.
  • Industrial rectifiers.
  • Soft starters.
  • Semiconductor protection circuits.

Technical Specifications

Item number W300031
Catalogue No A070UD31KI400
Description Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 400A With Striker Slotted Blades short
EAN/UPC Code 3605340322552
Rated voltage AC UL 700 V
Rated voltage AC IEC 690 V
Ampere Rating 400 A
RoHS Compliant Yes
AC or DC AC
Speed/Characteristic aR
Fuse Size 31
Mounting Bolted
Clearing I2t At Rated Voltage 110000 A²s
Melting I2t 19000 A²s
AC Max I.R./Breaking Capacity I1: 200 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 129 mm
Product Height 56.5 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 1.203 kg
Sell Pack Width 157 mm
Sell Pack Length 166 mm
Sell Pack Height 62 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.401 kg
Power Dissipation at Rated Current Value 68 W
HS Code 85361090
Country of Manufacture France
Fuse Type Semiconductor
Fuse Class aR
Voltage 690 V

Frequently Asked Questions

What is the Mersen W300031 used for?

It is designed to protect semiconductor devices such as IGBTs, thyristors and diodes used in industrial power electronic equipment.

What is the current rating of the W300031?

The fuse has a 400 A current rating.

What voltage is the fuse rated for?

The W300031 is rated for 690 V AC (IEC) and 700 V AC (UL) systems.

What does the aR characteristic mean?

The aR characteristic provides ultra-fast short-circuit protection for semiconductor devices while allowing normal operating currents to pass.

Where is this fuse commonly installed?

It is commonly installed in variable speed drives, industrial converters, UPS systems, renewable energy equipment and other power electronic installations.

Trusted by Industrial Engineers Worldwide

Mersen Protistor® semiconductor fuses are widely trusted by engineers and OEM manufacturers to provide dependable protection for critical power electronic equipment in demanding industrial environments.

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