摘要 |
An electronic switch circuit (10) including an electromagnetic relay device (18) having an electromagnet (20) and at least two contacts (21), a controlled semiconductor device (22), a semiconductor command circuit (24) for controlling the controlled semiconductor device (22), a relay command circuit (28) for controlling the relay device (18) and the semiconductor command circuit (24), an overload sensor (26) for reporting the relay command circuit (28) of a current overload, a resistor (32), and an inducer (34); wherein when the contacts (21) are disconnected, the resistor (32) experiences a higher current load, automatically signals the semiconductor command circuit (24), which turns the controlled semiconductor device (22) off; and further wherein the inducer (34) generates an induction field of a magnitude sufficient to induce the electromagnet (20) of the electromagnetic relay device (18) to disconnect the contacts when the inducer (34) experiences a current overload above a predetermined threshold.
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