| 摘要 |
PURPOSE:To provide the timer function to a switch, by making induced voltages of secondary windings almost equal, when a rated load current flows to the primary winding of a transformer and a minute load current flows through an impedance element and the secondary winding of the transformer. CONSTITUTION:A power supply terminal of a timer 9 is connected in parallel with a secondary winding 5b of a transformer 5 having a low impedance primary winding 5a, and a commercial power supply 2 is applied to a winding 5a of the transformer 5 via a contact 11a of a timer switching contact 11 of a timer 9 and a load 1. The power supply 2 is applied to the winding 5b of the transformer 5 via a series circuit of an impedance element 6 and another contact 11b of the contact 11 and the load 1. In this case, the winding ratio of the transformer 5 and the value of the element 6 are set so that the induced voltages in the winding 5b when the rated load current flows through the winding 5a of the transformer 5 becomes almost equal to those when a minute load current flows through the element 6 and the winding 5b of the transformer 5. |
