| 摘要 |
PURPOSE:To enable to block a rush current even at the reclosing time immediately after the interruption by turning the switch connected in parallel with a resistor for blocking the rush current OFF when the voltage produced at the auxiliary winding reaches the value smaller than the preset value. CONSTITUTION:A smoothing capacitor C0 is connected in parallel with a rectifier DB, an inverter INV is driven by the output, and a rush current blocking resistor R0 and a switch S2 connected in parallel with the resistor are inserted into a capacitor C0 charger. The voltage produced at the auxiliary winding N3 of an oscillation transformer OT is rectified and smoothed, added through a Zener diode ZD to a timer which has a capacitor C3 and a transistor Q3, a relay Ry is energized to turn OFF the switch S2. Accordingly, the period from when the power source switch S1 is turned OFF to when the switch S2 is turned OFF can be shortened, and the rush current can be completely blocked even if reenergized immediately after the S1 is turned OFF. |
