MERSEN FUSE A 070 URD 31 LI 0550 A070URD31LI0550

MERSEN FUSE A 070 URD 31 LI 0550 A070URD31LI0550

Reliable circuit protection fuse for power semiconductors rated at 550A, 690VAC IEC, and 700VAC UL with striker indication and slotted blades.

SKU: C300704Alt SKU: A070UD31LI550MPN: C300704
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List Price £179.91 ex VAT
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Sold in packs of 3

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Why Choose the Mersen C300704 High-Speed Semiconductor Fuse?

The Mersen C300704 is a premium Protistor® Size 31 high-speed semiconductor fuse engineered to deliver outstanding protection for sensitive power electronic components in demanding industrial environments. As part of the trusted Mersen Protistor® Size 31 aR series, it provides ultra-fast fault interruption to protect IGBTs, thyristors, diodes and other semiconductor devices from damaging short-circuit currents.

Designed for modern power conversion equipment, the C300704 combines low let-through energy with an exceptionally high breaking capacity to maximise equipment protection while reducing costly downtime. Precision die-cut fuse elements, silver-plated contacts and solidified sand construction ensure dependable long-term performance in demanding applications.

With a 550 A current rating and a 690 V AC IEC / 700 V AC UL voltage rating, the Mersen C300704 is ideally suited for variable frequency drives, industrial inverters, UPS systems and renewable energy converters. It features long slotted blade terminals and an integrated striker indicator for simplified monitoring and maintenance.

Key Advantages

  • Ultra-fast aR semiconductor fuse for protecting power electronic equipment.
  • 550 A current rating for demanding industrial applications.
  • 690 V AC IEC / 700 V AC UL voltage rating.
  • Very low let-through energy helps minimise semiconductor damage.
  • Integrated striker indicator for maintenance and remote monitoring.
  • High 200 kA AC breaking capacity for reliable fault protection.

Key Features

  • Mersen Protistor® Size 31 aR series.
  • 550 A rated current.
  • 690 V AC IEC / 700 V AC UL rated voltage.
  • Ultra-fast aR operating characteristic.
  • Long slotted blade terminals.
  • Integrated striker indication.
  • Silver-plated contact surfaces.
  • Designed for protecting IGBTs, SCRs, thyristors and power semiconductor modules.

Reliable Protection for Industrial Power Electronics

High-speed semiconductor fuses are specifically engineered to protect valuable power electronic components by interrupting fault currents before they can damage sensitive semiconductor devices. Their low I²t performance helps reduce thermal stress, improve equipment reliability and minimise maintenance costs.

The Mersen Protistor® Size 31 range is widely specified by OEMs and industrial engineers for protecting variable frequency drives, industrial motor drives, renewable energy converters, UPS systems and power conversion equipment where dependable semiconductor protection is essential.

Typical Applications

  • Variable frequency drives (VFDs).
  • Industrial motor drives.
  • Power converters and inverters.
  • UPS and backup power systems.
  • Renewable energy converters.
  • Protection of IGBT, SCR and diode modules.

Technical Specifications

Item number C300704
Catalogue No A070UD31LI550
Description Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 550A With Striker Slotted Blades long
EAN/UPC Code 3605340332469
Rated voltage AC UL 700 V
Rated voltage AC IEC 690 V
Ampere Rating 550 A
RoHS Compliant Yes
AC or DC AC
Speed/Characteristic aR
Fuse Size 31
Mounting Bolted
Clearing I2t At Rated Voltage 310000 A²s
Melting I2t 52000 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 148.6 mm
Product Height 56.5 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 1.2519 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 0.4173 kg
Power Dissipation at Rated Current Value 75 W
HS Code 85361090
Country of Manufacture France
Fuse Type Semiconductor
Fuse Class aR
Voltage 690 V

Frequently Asked Questions

What is the Mersen C300704 used for?

The C300704 is a high-speed semiconductor fuse designed to protect IGBTs, thyristors, diodes and other power electronic components against short-circuit faults.

What is the current rating of this fuse?

The fuse has a 550 A current rating.

What voltage is the fuse rated for?

It is rated for 690 V AC (IEC) and 700 V AC (UL).

What type of terminals does the fuse use?

The Mersen C300704 is supplied with long slotted blade terminals for secure installation in compatible fuse assemblies.

Does the fuse include an indicator?

Yes. The fuse incorporates an integrated striker indicator that can be used for visual or remote indication when installed with suitable accessories.

Trusted for Semiconductor Protection Worldwide

Mersen Protistor® semiconductor fuses are trusted by OEMs, panel builders and industrial engineers worldwide for delivering dependable protection of critical power electronic equipment.

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