| 摘要 |
PURPOSE: An automatic switch and a controlling method therefor are provided to detect short circuits and prevent the fusing of relay nodes by using two relay elements capable of separately turning on and off a supply line of a load. CONSTITUTION: An automatic switch includes two relay elements(11,12) and a driver. Each of the relay elements has one coupling point(SW1,SW2) inserted to each of a supply line of a load and is driven to switch the coupling point respectively. The load is switched by using the two relay elements. The driver includes an image current changer(17), a short circuit detector(16), and a controller(13). The image current changer induces a current signal from a change on a load current. The short circuit detector converts the induced current signal to provide information on the short circuit. The controller drives or stops driving the relay elements to turn on or off the load(6), and determines whether short circuit occurs based on the information from the short circuit detector. The controller stops driving the relay elements, when short circuit occurs, to turn off the load and keeps inspecting the short circuit repeatedly to turn the load back on when the short circuit is overcome.
|
