| 摘要 |
Failsafe control circuit for electrical appliances whereby at least one electrical load ( 10 ) is activated, the control circuit comprising logic control means ( 1 ), operation switching means ( 8 ) between said electrical load ( 10 ) and a supply voltage (V), and a first drive circuit ( 6 ) which receives a first command signal ( 4 ) from the logic control means ( 1 ), said first drive circuit ( 6 ) acting on said operation switching means ( 8 ). It also comprises security switching means ( 9 ) between the electrical load ( 10 ) and the supply voltage (V), and a second drive circuit ( 7 ) which receives a second command signal ( 5 ) from the logic control means ( 1 ), said second drive circuit ( 7 ) acting on the security switching means ( 9 ) so that it closes said security switching means ( 9 ) only if said second command signal ( 5 ) is a pulse signal.
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