| 摘要 |
<p>PURPOSE:To prevent the effect of electrostatic induction of the primary conductor as well as to simply perform a test without applying a current on the primary conductor by a method wherein a coil for testing is wound on the secondary coil of an air-core current transformer, and one end of said coil for testing is earthed. CONSTITUTION:A coil 3 to be used for a testing is wound on the air-core secondary coil 2 of an air-core current transformer. One end of the coil 3 is earthed. When a current is applied to the primary conductor 1, the induction voltage corresponding to the voltage of the conductor 1 is induced on the coil 3 by the electrostatic induction, and the voltage corresponding to the conductive current of the conductor 1 and that of the phase lagged by 90 deg. is induced. Then, as the coil 3 is earthed, the coil 2 is not subjected to the effect of electrostatic induction. Also, the current corresponding to the current to be used for testing is outputted to the coil 2 by applying the testing current to the coil 3.</p> |
