| 摘要 |
PROBLEM TO BE SOLVED: To check the ON/OFF of a switch and keep safety without providing a protective device with a protective circuit separately. SOLUTION: This protective device is provided in one part of the path for parts that electromagnetic type switches 1 and 2 connected in series between terminal T1 and T2 protect. As for the switches 1 and 2, on/off is controlled by the drive currents that flow to driving coils 3 and 4. In a voltage detecting circuit 51 connected with both ends of the switch 1, the potential difference between the terminals of the switch 1 is detected, and it is supplied with the control state of the switch 1 from a control circuit 54, and the operation state of the switch 1 is judged. In a voltage detecting circuit 52 connected with both ends of the switch 2, the potential difference between the terminals of the switch 2 is detected, and also it is supplied with the control state of the switch 2 from the control circuit 54, and the operation state of the switch 2 is judged. When the control circuit 54 is supplied with the control signal from the control suspension circuit 53, it supplies a drive circuit 55 with a control signal for turning on or turning off the switches 1 and 2. COPYRIGHT: (C)2005,JPO&NCIPI
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