felindikator

Felindikator, a term used in Swedish and Norwegian technical literature, refers to a fault indicator device used in electrical power systems to detect and signal faults on lines or equipment. These devices are installed on transmission and distribution networks to enable rapid fault localization, improve restoration times, and support protection schemes and maintenance planning.

Principle of operation: A felindikator continuously monitors electrical parameters such as current, voltage, impedance, and transient waveforms. When a fault or abnormal condition occurs—such as a short circuit, ground fault, or arcing event—the device detects characteristic changes and emits a fault indication. Outputs can include local indicators (LEDs or contacts) and remote signals transmitted to SCADA, a distribution management system, or dedicated fault-location software. Different sensing approaches exist, including current-based thresholding, traveling-wave sensing for fault transients, impedance-based methods, and arc-fault detection.

Types and deployment: Common configurations include line fault indicators mounted on overhead conductors or attached to underground cables, feeder fault indicators at sectionalizing points, and transformer fault indicators. They may be standalone units or integrated with other equipment such as sectionalizers, reclosers, or remote terminal units. Some systems also provide situational information like fault type, direction, and estimated location to assist operators.

Communication and impact: Modern felindikator systems use wireless (RF), cellular (GPRS/LTE/NB-IoT), or power-line communication to relay fault data. By enabling quicker fault location and isolation, utilities can reduce outage duration, minimize customer impact, and improve reliability metrics such as SAIDI and SAIFI. The technology is widely used in urban and rural networks, including underground and submarine cable systems.

Limitations: Costs, potential false positives, environmental exposure, and ongoing maintenance can affect performance and adoption.