Switching electrical load using parallel switching circuit by closing and opening single contact when supply voltage polarity changes from switch-on to switch-off process

摘要

The parallel circuit consists of one semiconductor switch (6) and one or more electromechanical switches (5, 5a etc.). When the semiconductor switch is switched on and off, and during operation the contacts of the electromagnetic switches are conducting. A single contact (4) that is connected in parallel with the semiconductor switch is closed and opened when the polarity of the applied half wave of the supply voltage changes from a switch-on process to a switch-off process. The contacts of several switches (5, 5a etc.) may close as the first and open as the last in sequence and in turn, each being closed and opened when the polarity changes from switch-on process to switch-on process. An apparatus based on the method is also claimed.