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MERSEN FUSE 6,9 URZ 17 P 35 BS17UZ69V35P
The Protistor® 17×49 aR fuse-link delivers dependable circuit protection for industrial applications, featuring a 35A rating and compliance with IEC 60269 and BS standards for enhanced safety. Its compact 17×49 mm design ensures easy integration into space-constrained panels while supporting operational voltages up to 690VAC.
£38.69
Why Choose the Mersen W221256 BS17UZ69V35P Semiconductor Fuse?
The Mersen W221256 BS17UZ69V35P is a high-speed Protistor® BS88-4 semiconductor fuse-link designed to provide rapid short-circuit protection for sensitive power semiconductor devices. Featuring an aR operating characteristic, this fuse delivers extremely fast fault clearance to protect IGBTs, thyristors, diodes, GTOs and other semiconductor components used in industrial power electronics.
Rated at 35 A with a 690 V AC IEC and 700 V AC UL voltage rating, the BS17UZ69V35P is suitable for variable speed drives, UPS systems, inverters, rectifiers and similar equipment operating at up to 700 V. The integrated striker indicator provides convenient remote indication capability when used with an optional microswitch.
Manufactured using pure silver fuse elements embedded in solidified silica sand, the W221256 provides excellent current limitation, low I²t values and a very high breaking capacity, helping minimise damage during fault conditions while improving equipment reliability and reducing maintenance costs.
Key Advantages
- High-speed aR semiconductor protection.
- 35 A current rating for industrial power electronics.
- 690 V AC IEC / 700 V AC UL rated.
- 200 kA breaking capacity.
- Integrated striker indicator for remote status indication.
- Low I²t reduces stress on semiconductor devices.
- Compact BS88-4 17 × 49 mm construction.
Key Features
- Manufacturer: Mersen
- Series: Protistor® BS88-4
- Model: BS17UZ69V35P
- Manufacturer SKU: W221256
- Fuse class: aR high-speed semiconductor fuse
- Integrated striker indication system.
- Copper L-bracket terminals.
- Ceramic body with pure silver fuse elements.
- Designed for bolted mounting.
High-Speed Protection for Sensitive Power Electronics
The Mersen W221256 is specifically designed to interrupt high fault currents before they can damage expensive semiconductor devices. Its low let-through energy and high interrupting capacity make it an ideal choice for protecting modern industrial power electronics operating under demanding conditions.
Unlike full-range gR semiconductor fuses, the BS17UZ69V35P uses an aR characteristic, meaning it provides rapid short-circuit protection and should be used alongside suitable overload protection where required by the equipment design.
Typical Applications
- Variable frequency drives (VFDs).
- Industrial inverters.
- Rectifiers.
- UPS systems.
- Motor drives.
- Power converters.
- Industrial automation equipment.
- Semiconductor protection circuits.
Technical Specifications
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| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Size | 17x49 mm | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | W221256 | |
| Catalogue No | BS17UZ69V35P | |
| Description | British Standard fuse-link Protistor® 17x49 aR 690VAC IEC 35A With Striker | |
| EAN/UPC Code | 3605340251586 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 35 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 17x49 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 330 A²s | |
| Melting I2t | 53 A²s | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Indication System | Yes | |
| Indication System Type | Striker | |
| Connection/Terminal Material | Copper | |
| Connection/Terminal Type | L Brackets | |
| Product Diameter | 18.5 mm | |
| Product Width | 27 mm | |
| Product Length | 77.2 mm | |
| Product Height | 24 mm | |
| Sell Pack Quantity | 10 EA | |
| Sell Pack Weight | 0.5 kg | |
| Sell Pack Width | 110 mm | |
| Sell Pack Length | 250 mm | |
| Sell Pack Height | 30 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.05 kg | |
| Power Dissipation at Rated Current Value | 11 W | |
| HS Code | 85361050 |
Frequently Asked Questions
What is the Mersen W221256 used for?
It provides high-speed short-circuit protection for semiconductor devices including IGBTs, thyristors, diodes and other power electronic components.
What is the current rating?
The W221256 has a rated current of 35 A.
What voltage is this fuse rated for?
It is rated at 690 V AC (IEC) and 700 V AC (UL).
What does the aR characteristic mean?
An aR fuse provides high-speed short-circuit protection for semiconductor devices but requires separate overload protection where applicable.
Does this fuse include an indicator?
Yes. The BS17UZ69V35P incorporates a striker indicator that can operate a compatible microswitch for remote indication.
What equipment is this fuse commonly installed in?
It is widely used in industrial drives, UPS systems, inverters, rectifiers, power converters and similar semiconductor-based equipment.
Trusted Semiconductor Protection from Mersen
Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, machine builders and maintenance engineers to protect valuable semiconductor equipment in demanding industrial power applications.
