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MERSEN FUSE 6,9 URY 17/90 BS17UY69V90

MERSEN FUSE 6,9 URY 17/90 BS17UY69V90

The Protistor® 17×49 aR fuse-link offers reliable protection for semiconductor devices and power circuits, designed in accordance with BS, IEC, and VDE standards. With a compact 17x49mm size and 90A rating at 690VAC, it ensures fast-acting response and low energy let-through for critical applications.

SKU: T221254Alt SKU: BS17UY69V90MPN: T221254
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List Price £21.71 ex VAT
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Why Choose the Mersen T221254 Protistor® Semiconductor Fuse?

The Mersen T221254 is a high-performance Protistor® BS88-4 semiconductor fuse engineered to provide fast and reliable protection for sensitive power semiconductor devices. Designed for demanding industrial applications, this 17 x 49 mm British Standard fuse-link delivers exceptional protection for power electronics including diodes, thyristors, IGBTs and GTOs used in drives, converters and power control equipment.

As part of the renowned Mersen Protistor® range, the T221254 is manufactured using pure silver fuse elements embedded within solidified sand, providing excellent arc control, low let-through energy (I²t) and high breaking capacity. This advanced construction helps minimise damage to expensive semiconductor components during fault conditions while improving overall system reliability.

Rated at 90 A with a 690 V AC operating voltage, the Mersen T221254 complies with IEC 60269-1, IEC 60269-4, BS88-4 and VDE 636-23, making it suitable for use in industrial power conversion systems and electrical protection applications worldwide.

Key Advantages

  • Fast-acting aR semiconductor protection fuse.
  • 90 A current rating for industrial power electronics.
  • 690 V AC operating voltage.
  • Protects diodes, thyristors, IGBTs and GTO devices.
  • High breaking capacity for demanding fault conditions.
  • Complies with international IEC and BS standards.

Key Features

  • Manufacturer: Mersen.
  • Series: Protistor® BS88-4 17 x 49 aR URZ/URY.
  • Model: T221254.
  • Catalogue number: BS17UY69V90.
  • Current rating: 90 A.
  • Rated voltage: 690 V AC.
  • Operating class: aR semiconductor protection.
  • Fuse size: 17 x 49 mm.
  • Pure silver fuse elements for rapid fault interruption.
  • Suitable for protection of semiconductor power devices.

Reliable Protection for Power Electronics

Semiconductor fuses are specifically designed to provide ultra-fast fault protection for sensitive electronic power devices. Their rapid response limits fault energy before damage can occur, helping to extend equipment life and reduce downtime in industrial electrical systems.

The Mersen Protistor® range is widely used in variable speed drives, UPS systems, power converters, battery storage systems, soft starters and renewable energy installations where dependable semiconductor protection is essential.

Typical Applications

  • Variable frequency drives (VFDs).
  • Power converters and inverters.
  • Industrial motor drives.
  • UPS systems.
  • Renewable energy power electronics.
  • Semiconductor protection within switchgear and control panels.

Technical Specifications

Item number T221254
Catalogue No BS17UY69V90
Description British Standard fuse-link Protistor® 17x49 aR 690VAC IEC 90A
EAN/UPC Code 3605340251562
Rated voltage AC IEC 690 V
Ampere Rating 90 A
RoHS Compliant Yes
AC or DC AC
Speed/Characteristic aR
Fuse Size 17x49
Mounting Bolted
Clearing I2t At Rated Voltage 3250 A²s
Melting I2t 520 A²s
AC Max I.R./Breaking Capacity I1: 200 kA
Connection/Terminal Material Copper
Connection/Terminal Type L Brackets
Product Diameter 18.5 mm
Product Length 77.2 mm
Sell Pack Quantity 10 EA
Sell Pack Weight 0.35 kg
Sell Pack Width 100 mm
Sell Pack Length 195 mm
Sell Pack Height 25 mm
Product group Semiconductor Protection Fuses
Body/Insulating Material Ceramic
Product Weight 0.035 kg
Power Dissipation at Rated Current Value 27 W
HS Code 85361090
Fuse Type Semiconductor
Fuse Size 17x49 mm
Fuse Class aR
Voltage 690 V

Frequently Asked Questions

What is the Mersen T221254 used for?

It is designed to provide ultra-fast protection for semiconductor devices including IGBTs, thyristors, diodes and other power electronic components.

What is the current rating of this fuse?

The Mersen T221254 has a rated current of 90 A.

What voltage is the fuse designed for?

The fuse is rated for operation on electrical systems up to 690 V AC.

What type of fuse characteristic does it use?

The T221254 is an aR semiconductor fuse, providing partial-range protection specifically for semiconductor devices.

Which standards does the fuse comply with?

It complies with IEC 60269-1, IEC 60269-4, BS88-4 and VDE 636-23 standards for semiconductor fuse-links.

Trusted by Power Electronics Engineers Worldwide

Mersen Protistor® semiconductor fuses are trusted by OEMs, panel builders and electrical engineers worldwide to protect critical semiconductor devices in demanding industrial power conversion applications.

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