NONCONTACT PREVENTION CIRCUIT OF LEAD SWITCH INSTALLED IN MECHANICAL METER AND METERING DEVICE COMPRISING THE SAME

摘要

PURPOSE: A noncontact prevention circuit of a lead switch installed in a mechanical meter and a metering device comprising the same are provided to prevent a mis-operation of a lead switch. CONSTITUTION: The first resistor(311) is applied with a DC voltage, and a capacitor(336) is connected between one end of the first resistor and a ground. The second resistor(312) is connected to another end of the first resistor. And a switching device(338) is connected between the second resistor and the lead switch, and is turned on when an input voltage becomes above a fixed level. When the lead switch is turned on, a voltage charged in the capacitor is discharged to flow a current to the lead switch, and thus unnecessary material attached to leads in the lead switch are melt down and thus electrical contact between leads is improved.