| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a residual current detector capable of accurately detecting residual current with an especially simple and cheap constitution simultaneously detecting and responding to various accidents in a residual current detector detecting the current value of the residual current detected with a residual current transformer. SOLUTION: The output signal line 10 of a residual current meter 1 arranged on lines 100u, 100V, 100W of three-phase alternating current is connected to input terminals 2a, 2b of an operator amplifier 2 constituted of a current-voltage converter circuit. By this, the residual current flowing in the lines 100U, 100V and 100W can be accurately detected with a simple and cheap constitution and without using a fine and expensive apparatus such as a microampere meter and the like.</p> |
