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MERSEN FUSE 6,9 URZ 17 P 40 BS17UZ69V40P
The Protistor® BS17UZ69V40P fuse-link is engineered to British Standard dimensions (17×49 mm) and optimised for reliable short-circuit protection in demanding industrial and electrical distribution systems up to 690 VAC. This 40A aR-class fuse delivers fast, precise interruption of fault currents to safeguard semiconductors and sensitive components.
£38.96
Why Choose the Mersen X221257 BS17UZ69V40P Semiconductor Fuse?
The Mersen X221257, catalogue number BS17UZ69V40P, is a high-speed Protistor® BS88-4 semiconductor fuse-link engineered to provide superior protection for sensitive power semiconductor devices. Featuring an ultra-fast aR operating characteristic, it rapidly clears short-circuit faults to safeguard IGBTs, thyristors, diodes, GTOs and other power semiconductor devices used in demanding industrial applications.
Rated at 40 A with 690 V AC (IEC) and 700 V AC (UL) ratings, the BS17UZ69V40P is ideal for variable speed drives, UPS systems, small inverters, rectifiers and industrial power converters. Its integrated striker indicator enables fast visual identification of an operated fuse and can operate a compatible microswitch for remote indication.
Manufactured using Mersen's proven Protistor® technology with pure silver elements embedded in solidified sand, the fuse delivers excellent current limitation, low let-through energy and a high interrupting capacity to minimise damage to expensive semiconductor equipment.
Key Advantages
- Ultra-fast aR semiconductor protection.
- 40 A current rating.
- 690 V AC IEC / 700 V AC UL ratings.
- Integrated striker indicator for local or remote signalling.
- 200 kA AC breaking capacity.
- Excellent current limitation with low I²t.
- Compact BS88-4 17 × 49 mm construction.
- Suitable for demanding industrial power electronic applications.
Key Features
- Manufacturer: Mersen
- Series: Protistor® BS88-4 17 × 49 aR URZ/URY
- Manufacturer SKU: X221257
- Catalogue number: BS17UZ69V40P
- Fuse class: aR
- 17 × 49 mm British Standard fuse-link.
- Integrated striker indicator.
- Bolted copper L-bracket terminals.
- UL Recognised and IEC compliant.
- RoHS compliant.
Designed for Critical Semiconductor Protection
The Mersen X221257 is specifically engineered for the protection of modern semiconductor devices used in industrial power conversion systems. Its ultra-fast aR characteristic limits fault energy before semiconductor devices can be damaged, helping maximise equipment reliability and minimise costly downtime.
As an aR semiconductor fuse, the BS17UZ69V40P is intended primarily for short-circuit protection. Suitable overload protection should also be incorporated where required by the equipment manufacturer and applicable electrical standards.
Typical Applications
- Variable frequency drives (VFDs).
- Small industrial inverters.
- UPS systems.
- Industrial motor drives.
- Power converters.
- Rectifiers.
- 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 | X221257 | |
| Catalogue No | BS17UZ69V40P | |
| Description | British Standard fuse-link Protistor® 17x49 aR 690VAC IEC 40A With Striker | |
| EAN/UPC Code | 3605340251593 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 40 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 17x49 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 430 A²s | |
| Melting I2t | 69 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 | 13.5 W | |
| HS Code | 85361050 |
Frequently Asked Questions
What is the Mersen X221257 used for?
It provides ultra-fast short-circuit protection for semiconductor devices used in industrial power electronic equipment.
What is the current rating?
The Mersen X221257 has a rated current of 40 A.
What voltage is this fuse rated for?
The fuse is rated at 690 V AC (IEC) and 700 V AC (UL).
Does this fuse include a striker indicator?
Yes. The BS17UZ69V40P incorporates an integrated striker indicator for local indication or remote signalling.
What does the aR classification mean?
An aR fuse provides ultra-fast short-circuit protection for semiconductor devices and is intended for use alongside suitable overload protection.
What is the interrupting capacity?
The fuse has a maximum AC breaking capacity of 200 kA.
Trusted by Industry
Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, panel builders and maintenance engineers to protect high-value semiconductor equipment operating in demanding industrial environments.
