| 摘要 |
PURPOSE:To prevent the failure due to unstable control output caused at power supply application and production of power failure, by providing the control FF with the corresponding terminal unit controlled for the power application to the load according to the operation of control relay controlled with the terminal unit. CONSTITUTION:When the power supply Vcc rises as (a) with the restoration of transmission signal, the output of the delay circuit 2 is as shown in (b) and FF13 is reset with the signal like (c). This is because the output of FF13 is unstable the same as the latch output at the application of power supply. Since the output of FF13 and the latch output are fed to the switching element 11 via the AND circuit 15, the latch output is not delivered to the element 11 at the application of power supply, and when the terminal unit address is in agreement with the transmission signal and input to FF13 as clock as (e), the output of FF13 made as (f), and the output of the AND circuit 15 is obtained as (g) with this output and the latch output of (d) to drive the control relay 10. Accordingly, at the restoration of power supply, no load unstable state is obtained and the rush current to the load can be avoided. |
