| 摘要 |
PURPOSE:To suppress a rush current at the time of turning ON a power source by monitoring the charging voltage of a capacitor and shortcircuiting a resistor in series with a capacitor when becoming the prescribed charging voltage. CONSTITUTION:A series circuit of a Zener diode ZD and a relay RL is connected in parallel with capacitor C. The rectified output voltage E is applied by turning ON a power source, and the capacitor C is charged in the polarity, as shown, through a resistor R. When the charging voltage VC of the capacitor C becomes the prescribed voltage, an operating current flows to the relay RL through the diode ZD. Accordingly, a contact rl becomes ON, and the resistor R is shortcircuited. Thus, when becoming the prescribed charging voltage near the completion of charging in response to the capacity of the capacitor C, the resistor R can be shortcircuited. Consequently, even if the capacity of the capacitor is irregular, the rush current when the resistor is shortcircuited can be reduced. |
