Fault current limiter FC-Protector

When planning or modifying electrical systems very high short-circuit fault levels are common problems in high power medium voltage systems. Those short-circuit faults can lead to severe damage of the installed electrical equipment. Reducing the fault level not only protects the electrical installation but also reduces the potential risk for the surrounding environment.

The FC-Protector consists of compact power part units (including insert holder with impulse transformer and current transformer, and insert) to be installed in each phase of the medium voltage system. Fault currents are detected by the control unit QR6-B of the FC-Protector which continuously monitors the instantaneous current.

The copper bridge (main current path) inside the sealed insert of the FC-Protector carries the continuous current in normal operating condition. In case of a fault current the main current path is immediately opened, triggered by the control unit QR6-B. The short-circuit current commutates to a parallel fuse with high breaking capacity, which limits the short-circuit current during the first rise within less than a quarter cycle.

Based on the long-term-proven and highly reliable I_s-limiter technology available since 1958, with more than 3000 installations around the world, the FC-Protector is developed to meet the requirements for indoor and outdoor applications.

Key benefits

• Standardized and compact solution for indoor and outdoor applications
• Short lead and response times due to standardized engineering process
• Fast and easy implementation
• Plug-and-play commissioning

Key features

• Available as individual components covering medium-voltage ratings up to 17.5 kV, 2,500 A and 63 kA rms breaking capability
• Flexible use for indoors and outdoors
• Tripping value based on instantaneous current
• Standardized engineering and documentation
• Standardized interfaces
• Standard web browser used to check the current system status of an ABB Relion® relay