| 摘要 |
An electric leakage detecting system is provided to allow a manager to remotely monitor various data or alarms through an output unit to communicate with a remote control device. An analog/digital converting unit(61) converts an analog value into a digital value. A digital/analog converting unit(51) converts the digital value into the analog value. An analog multiplying unit(52) multiplies two analog components. A setting unit(63) sets and inputs various data. A display unit(64) displays the various data or alarms. An operation control unit(62) has an operation function. A memory unit(66) stores the various data. A voltage detecting device(22a,22b) detects a voltage component of a power line(3) to accurately detect active leakage current. A voltage detecting unit(31) converts the voltage component into a predetermined voltage size. A voltage filter unit(32) extracts the voltage component of a commercial frequency component from the converted voltage component(Va1). A 90 degree phase shifting unit(33) shifts a phase of voltage(Va2) of the commercial frequency component by 90 degrees. A zero phase current transformer(10) detects zero phase leakage current flowing between the power line and the ground. A current/voltage converting unit(41) converts a current value of the zero phase leakage current into a voltage value. An amplifying unit(42) amplifies the zero phase leakage current. A current filter unit(43) extracts a zero phase leakage current component(Io1) of the commercial frequency component through the voltage filter unit. A synchronous detecting unit(44) synchronously detects the zero phase leakage current component of the commercial frequency component, the voltage component of the commercial frequency component, and the 90 degree shifted voltage component. A reactive current compensating winding(21) has an auxiliary winding function. A compensating filter unit(53) flows current to the reactive current compensating winding of the zero phase current transformer. An input/output unit(65) allows a manager to control a system in a remote place. |
