| 摘要 |
<p>An improved switching control apparatus (1) for switching a number of alternating current (AC) devices (20), such as AC vend motors, uses a reduced number of AC power switching elements (10) such as relays by dividing the AC devices into two groups and using one switching element (K7) to select which of the two groups is to be selected, and using an additional number of AC power switching elements (K1-K6) each of which is connected to one of the AC devices in each of the two groups to select which one of the AC devices is to be activated. Preferably, a further AC power switching element (Q1) is used to control the flow of power to the group determining AC power switching element so that switching transients can be minimized.</p> |
