Why Choose the Mersen N221249 High-Speed Semiconductor Fuse?
The Mersen N221249 is a premium high-speed semiconductor fuse developed to provide rapid short-circuit protection for sensitive power electronic equipment. As part of the renowned Mersen Protistor® BS88-4 URZ/URY series, it delivers exceptional current limiting performance and high breaking capacity for demanding industrial applications.
Manufactured using high-purity silver fuse elements embedded in solidified silica sand, the N221249 is engineered to minimise arc energy and reduce let-through current during fault conditions. This advanced construction helps protect valuable semiconductor devices such as IGBTs, SCRs, thyristors and diodes while improving equipment reliability and reducing maintenance costs.
With a rated current of 45 A and a 690 V AC IEC voltage rating, the Mersen N221249 is ideal for protecting variable frequency drives, rectifiers, inverters, UPS systems and industrial power converters. Its compact 17 × 49 mm BS88-4 fuse-link format offers straightforward installation within compatible fuse holders and semiconductor protection assemblies.
Key Advantages
- High-speed semiconductor fuse designed for industrial power electronics.
- 45 A rated current for semiconductor protection applications.
- 690 V AC IEC voltage rating suitable for industrial systems.
- aR operating class provides dedicated semiconductor short-circuit protection.
- High breaking capacity and excellent current-limiting performance.
- Compact BS88-4 design simplifies installation and replacement.
Key Features
- Mersen Protistor® BS88-4 URZ/URY series.
- 45 A nominal current rating.
- 690 V AC IEC rated voltage.
- 700 V AC UL rated voltage.
- aR partial-range semiconductor protection.
- Compact 17 × 49 mm fuse-link.
- Optional low-voltage trip indicator compatibility.
- Designed for converters, drives and power semiconductor protection.
Reliable Protection for Industrial Power Electronics
High-speed semiconductor fuses such as the Mersen N221249 interrupt fault currents before excessive energy reaches sensitive semiconductor devices. This rapid response helps reduce thermal stress, improve system reliability and extend the service life of industrial power electronics.
The Protistor® BS88-4 range has been developed specifically for the protection of diodes, thyristors, GTOs and IGBT devices used in modern power conversion equipment. Its international approvals make it suitable for use in industrial systems worldwide.
Typical Applications
- Variable frequency drives.
- Industrial motor control systems.
- Power converters and rectifiers.
- Industrial inverters.
- UPS systems.
- Power electronic and automation equipment.
