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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.
£11.94
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.
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.
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| Fuse Type | Semiconductor | |
|---|---|---|
| Fuse Size | 17x49 mm | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| 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 |
It is designed to provide ultra-fast protection for semiconductor devices including IGBTs, thyristors, diodes and other power electronic components.
The Mersen T221254 has a rated current of 90 A.
The fuse is rated for operation on electrical systems up to 690 V AC.
The T221254 is an aR semiconductor fuse, providing partial-range protection specifically for semiconductor devices.
It complies with IEC 60269-1, IEC 60269-4, BS88-4 and VDE 636-23 standards for semiconductor fuse-links.
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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