| 摘要 |
<p>PURPOSE:To provide a switch containing a current and voltage detecting device and a zero-phase current transformer which are hardly affected by external induction and can perform measurement with high accuracy. CONSTITUTION:A current and voltage detecting device 15 and a current detecting device 16 for zero phase current are provided in a case 1. A current sensor head and a voltage sensor head converting electric signals into light signals are respectively provided in the current and voltage detecting device 15, which transmits the light signals to be detected to a measuring portion through optical fibers 35, 42. The voltage sensor head converting the electric signal into the light signal is provided in the current detecting device 16 for the zero-phase current, which transmits the light signal to be detected to a measuring portion through optical fiber 56. Thereby it is possible to measure voltage/current accurately allowing no effect of external induction.</p> |
