Why Choose the Mersen W220957 BS17GB69V12 Semiconductor Fuse?
The Mersen W220957 BS17GB69V12 is a high-speed Protistor® British Standard fuse-link developed to protect power semiconductors and associated industrial electrical equipment. Its compact construction, extremely high breaking capacity and full-range gR operating characteristic make it suitable for circuits requiring dependable protection against both overloads and short circuits.
Rated at 12 A and 690 V AC under IEC specifications, the W220957 is designed for use in industrial drives, rectifiers, small inverters, UPS systems and other power-electronic installations. It also carries UL voltage ratings of 700 V AC and 600 V DC, supporting integration into equipment manufactured for different international markets.
The fuse uses a compact 17 × 49 mm format with copper L-bracket terminals for secure bolted installation. A breaking capacity of up to 200 kA at 690 V AC enables it to interrupt substantial prospective fault currents while limiting the energy passed to sensitive downstream components.
Key Advantages
- gR full-range protection for semiconductor circuits.
- Protects against both overload and short-circuit currents.
- 12 A current rating for lower-current industrial power electronics.
- 690 V AC IEC rating for demanding electrical installations.
- 200 kA breaking capacity for reliable fault interruption.
- Compact 17 × 49 mm design for space-conscious equipment.
- Supports selective coordination within suitable distribution circuits.
Key Features
- Mersen Protistor® BS88-4 semiconductor fuse-link.
- Catalogue number BS17GB69V12.
- Manufacturer item number W220957.
- 12 A rated current.
- 690 V AC IEC voltage rating.
- 700 V AC and 600 V DC UL voltage ratings.
- gR operating class.
- Extremely high breaking capacity.
- Ceramic body with copper L-bracket terminals.
- Bolted mounting arrangement.
- Version without an operation indicator.
Full-Range gR Semiconductor Protection
A gR fuse provides full-range protection for power semiconductor equipment, allowing it to respond to sustained overloads as well as severe short-circuit faults. This differs from an aR semiconductor fuse, which is primarily intended for partial-range short-circuit protection and may require separate overload protection.
The low melting and clearing I²t values of the Mersen W220957 help restrict the thermal energy transmitted during a fault. This assists in protecting sensitive components such as diodes, thyristors, rectifier assemblies and power-conversion modules from potentially costly damage.
Typical Applications
- Variable speed AC drives.
- Small industrial inverters.
- Rectifiers and power converters.
- Uninterruptible power supply systems.
- Semiconductor switching equipment.
- Industrial motor-control panels.
- Power distribution circuits requiring selective fuse coordination.
