METHOD FOR TESTING CONNECTING STATE AND PHASE OF UNDERGROUND DISTRIBUTION LINE

摘要

PURPOSE: A method for testing a connecting state and a phase of an underground distribution line is provided to quickly and exactly perform operations which discriminate the connecting state and phase of the underground distribution line. CONSTITUTION: Current transformers(CTx1,CTx2) of a transmitter generates and injects an injection driving wave in a cable. A frequency which is injected through the current transformers(CTx1,CTx2) is 625 Hz close to each frequency of tenth and first harmonic waves. The current transformers(CTx1,CTx2) are manufactured with a wide specification of a dynamic range. A receiver has a function which discriminates a connecting state and a phase of a line. A function is switched by exchanging a connector of a sensor. A search coil is substituted for a sensor in order to discriminate a connecting state of an underground distribution line. The search coil contacts with an armor of the cable.