| 摘要 |
PURPOSE:To turn off a load before a prescribed time of an automatic delay switch is elapsed by connecting a switch in parallel with a capacitor of a time constant circuit of an electronic timer. CONSTITUTION:When the switch SW1 is turned on, the capacitor C1 of the time constant circuit of the electronic timer is changed via a transformer CT, a diode bridge DB1 and a diode D1, a power control element TR is conducted by a control circuit X and the load L is turned on. When the charge of the capacitor C1 is discharged gradually via a resistor VR succeedingly, the control circuit X turns off the power control element TR and the load is turned off also after a prescribed time is elapsed. When the switch SW2 is turned on before the power control element TR is turned off, the capacitor C2 is discharged rapidly and the power control element TR is turned off by the control circuit X so as to turn off instantly the load. Thus, the load becoming unnecessary is turned off quickly and the power consumption is saved. |
