| 摘要 |
<p>A fault current sensor device (1) which can detect and distinguish abnormal current events such as momentary outage, sustained outage, normal overload, and inrush on an alternating current overhead or underground power transmission or distribution line (2). The sensing device (1) is attached to the power line (2) and, when a fault condition is detected, a Schmitt trigger (15) wakes up a microprocessor (11) from a sleep mode. The microprocessor distinguishes which one of the fault current conditions has occurred on the power line (2), and a transceiver (3) transmits an alarm signal to a designated ground station. The device (1) can be remotely programmed to alter its trigger or threshold level or time delay to reset the device (1) when a fault has occurred. When normal current levels return, the device can be reset by itself or remotely from the ground station. The fault sensor device is powered by capacitors (8) which are charged by photovoltaic cells (7) or a current transformer (18).</p> |
