| 摘要 |
PURPOSE:To reduce the floating capacity, BY using an AC power source in common to each of the contacts and then applying the full wave rectified DC voltage to each contact. CONSTITUTION:When a contact 3 is open, no current flows to a photocoupler 9 and the output of the coupler 9 is set at a high level. While if the contact 3 is closed, the current of a rectifying circuit 5 flows to the coupler 9 through a smoothing circuit 6 and a resistance 7. Thus the output terminal of the circuit 5 is set at a low level. Now if the capacity of a capacitor C in the circuit 6 is set at zero, the current is supplied to the coupler 9. In other words, the adverse effect due to floating capacity 4 can be eliminated without using a DC power source but by selecting properly the receiving elements at the side of the resistance 7, the coupler 9 and processors, respectively. |
