SKU: P300623Alt SKU: PC72UD13C500EFMPN: P300623
MERSEN FUSE 12,5 URD 72 EF 0500 12,5URD72EF0500

MERSEN FUSE 12,5 URD 72 EF 0500 12,5URD72EF0500

High-speed fuse designed for reliable protection of power semiconductors with 500A rating, integrated striker for indication, and open slot blades for easy installation.

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£240.00

Why Choose the Mersen P300623 Protistor® High-Speed Fuse?

The Mersen P300623 is a premium Protistor® Size 72 high-speed semiconductor fuse designed to provide ultra-fast protection for modern power electronic equipment. Engineered for demanding industrial applications, it protects diodes, thyristors and IGBT devices against damaging short-circuit and overcurrent conditions while helping maximise equipment reliability and minimise downtime.

Part of the advanced Mersen Protistor® Size 72 series, the P300623 features a robust square ceramic body with open slot blade terminals and an integrated striker indicator. Manufactured using die-cut silver fuse elements embedded in solidified sand, it delivers exceptionally low let-through energy and outstanding fault interruption performance for critical semiconductor protection applications.

Rated at 500 A with a 1250 V AC (IEC) / 1300 V AC (UL) voltage rating, the P300623 is ideally suited to industrial drives, UPS systems, renewable energy equipment, power converters and other high-performance electrical installations requiring dependable semiconductor protection.

Key Advantages

  • Ultra-fast aR semiconductor protection fuse.
  • 500 A current rating for high-power industrial applications.
  • 1250 V AC IEC / 1300 V AC UL voltage rating.
  • Protects diodes, thyristors and IGBT devices.
  • 126 kA AC breaking capacity.
  • Integrated striker indicator for simplified maintenance.

Key Features

  • Mersen Protistor® Size 72 series.
  • Catalogue number: PC72UD13C500EF.
  • 500 A rated current.
  • 1250 V AC IEC / 1300 V AC UL operating voltage.
  • aR ultra-fast semiconductor protection characteristic.
  • Open slot blade terminals.
  • Integrated striker indicator.
  • Silver-plated contacts with square ceramic body construction.

Technical Specifications

  • Manufacturer: Mersen
  • Series: Protistor® Size 72
  • Catalogue number: PC72UD13C500EF
  • Part number: P300623
  • Product type: High-speed semiconductor fuse
  • Current rating: 500 A
  • Rated voltage (IEC): 1250 V AC
  • Rated voltage (UL): 1300 V AC
  • Fuse characteristic: aR ultra-fast acting
  • Breaking capacity: 126 kA AC
  • Terminal type: Open slot blade terminals
  • Indicator: Integrated striker
  • Body style: Square body Size 72
  • Contact material: Silver-plated
  • RoHS compliant: Yes

Reliable Protection for Power Electronics

The Mersen P300623 has been developed for demanding power conversion equipment where semiconductor devices require rapid fault clearance. Its low I²t performance helps minimise thermal stress during fault conditions, reducing the risk of costly equipment damage and extending the service life of protected components.

Suitable for OEM installations and maintenance replacements, the P300623 provides dependable protection in industrial environments where high-speed semiconductor protection is essential for safe and reliable operation.

Typical Applications

  • Variable speed drives (VSDs).
  • Industrial power converters.
  • Renewable energy inverter systems.
  • Uninterruptible power supplies (UPS).
  • Motor drives and soft starters.
  • Industrial automation and power distribution equipment.

Technical Specifications

Item number P300623
Catalogue No PC72UD13C500EF
Description Square Body High-Speed Fuse Protistor® Size 72 aR 1250VAC IEC 1300VAC UL 500A With Striker Open Slot Blades
EAN/UPC Code 3605340331141
Rated voltage AC UL 1300 V
Rated voltage AC IEC 1250 V
Ampere Rating 500 A
AC or DC AC
Speed/Characteristic aR
Fuse Size 72
Mounting Bolted
Clearing I2t At Rated Voltage 465 kA²s
Melting I2t 57.1 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 Open Slot Blades
Product Width 59 mm
Product Length 149.4 mm
Product Height 63 mm
Sell Pack Quantity 3 EA
Sell Pack Weight 2.274 kg
Sell Pack Width 157 mm
Sell Pack Length 205 mm
Sell Pack Height 80 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.758 kg
Power Dissipation at Rated Current Value 98 W
HS Code 85351000

Frequently Asked Questions

What is the Mersen P300623 used for?

The P300623 is an ultra-fast semiconductor fuse designed to protect diodes, thyristors and IGBT devices against short-circuit and overcurrent faults.

What is the current rating of the P300623?

The Mersen P300623 has a continuous current rating of 500 A.

What voltage is the P300623 rated for?

The fuse is rated at 1250 V AC (IEC) and 1300 V AC (UL).

Does the P300623 include a striker indicator?

Yes. It incorporates an integrated striker indicator that can be used with a compatible microswitch for remote indication and maintenance monitoring.

Which applications commonly use this fuse?

The P300623 is commonly installed in industrial drives, power converters, UPS systems, renewable energy equipment and other semiconductor-based power conversion systems.

Trusted by Power Electronics Professionals Worldwide

Mersen Protistor® semiconductor fuses are trusted by OEMs, electrical engineers and industrial maintenance teams worldwide for reliable protection of high-value power electronic equipment.

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