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MERSEN FUSE 6,9 URZ 17/63 6,9URZ17/63
British Standard fuse-link Protistor® 17×49 aR 690VAC IEC 63A designed for semiconductor protection with high breaking capacity and rapid response.
£21.79
Why Choose the Mersen Q221251 Protistor® High-Speed Semiconductor Fuse?
The Mersen Q221251 is a Protistor® BS88-4 British Standard high-speed semiconductor fuse designed to provide exceptional protection for sensitive power semiconductor devices. Manufactured to IEC 60269-1, IEC 60269-4, VDE 636-23 and BS88-4 standards, it delivers extremely fast fault interruption for modern industrial power electronic equipment.
With a 63 A current rating, 690 V AC IEC / 700 V AC UL voltage rating and a 17 × 49 mm BS88-4 fuse-link design, the Q221251 offers reliable protection for diodes, thyristors, GTOs and IGBT devices used in drives, UPS systems, converters and industrial inverters. The fuse is manufactured using pure silver elements embedded in solidified sand, providing low let-through energy (I²t), excellent current limitation and a high breaking capacity.
As part of Mersen's internationally recognised Protistor® semiconductor protection range, the Q221251 helps reduce damage to expensive power electronics, minimise downtime and improve equipment reliability in demanding industrial environments.
Key Advantages
- Designed specifically for semiconductor protection.
- 63 A rated current.
- 690 V AC IEC / 700 V AC UL rated.
- Extremely fast-acting aR characteristic.
- Current-limiting design with low I²t.
- High 200 kA AC breaking capacity.
Key Features
- Manufacturer: Mersen.
- Series: Protistor® BS88-4.
- Catalogue number: BS17UZ69V63.
- 17 × 49 mm British Standard fuse-link.
- aR ultra-fast semiconductor protection.
- Pure silver fuse elements.
- Solidified sand arc-quenching construction.
- Suitable for worldwide industrial applications.
Reliable Protection for Power Electronics
The Mersen Q221251 has been engineered specifically for protecting semiconductor devices where conventional fuses may not react quickly enough. Its ultra-fast aR operating characteristic limits fault energy before excessive thermal stress can damage valuable power electronic components.
Typical installations include variable speed drives, UPS systems, industrial inverters, converters and similar equipment operating at up to 690 V AC, where dependable semiconductor protection is essential for maintaining system reliability.
Typical Applications
- Variable frequency drives (VFDs).
- Industrial UPS systems.
- Power converters.
- Industrial inverters.
- Motor drives.
- Semiconductor protection circuits.
Technical Specifications
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| Fuse Type | Semiconductor | |
|---|---|---|
| Fuse Size | 17x49 mm | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | Q221251 | |
| Catalogue No | BS17UZ69V63 | |
| Description | British Standard fuse-link Protistor® 17x49 aR 690VAC IEC 63A | |
| EAN/UPC Code | 3605340251531 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 63 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 17x49 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 1320 A²s | |
| Melting I2t | 210 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 | 19.5 W | |
| HS Code | 85361050 |
Frequently Asked Questions
What is the Mersen Q221251 used for?
It protects power semiconductor devices such as IGBTs, thyristors, diodes and GTOs used in industrial power electronic equipment.
What is the current rating?
The Mersen Q221251 has a rated current of 63 A.
What voltage is it designed for?
It is rated for 690 V AC (IEC) and 700 V AC (UL).
Does this fuse include an operation indicator?
No. The Q221251 is the non-indicating version. Mersen also offers a striker-equipped version under a different catalogue reference.
Where is the Q221251 commonly installed?
It is commonly installed in variable speed drives, UPS systems, industrial inverters, converters and similar power electronic equipment requiring high-speed semiconductor protection.
Trusted for Industrial Semiconductor Protection
Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, panel builders and maintenance engineers to protect critical industrial power electronic equipment with fast, reliable fault interruption.
