INITIAL CLEAR CIRCUIT

摘要

PURPOSE:To improve the generality of an initial clear circuit by providing a means which is a circuit being independent of a power source device, and varies the timing of a generated initial clear signal. CONSTITUTION:An independent initial clear circuit 22 is connected to a power source device 21. By this circuit 22, an AC power source supplied to an AC input terminal 31 is fed to a series circuit consisting of a light emitting element 34 of a photocoupler, transistor 35, etc., through a fuse 32 and a rectifying bridge 33. Also, a DC voltage VO outputted from the power source device 21 is applied to a DC input terminal 35, this voltage VO is applied to a series circuit, etc. consisting of a photodetector 37 of said photocoupler, etc., and this circuit is constituted as shown in the figure. In such a state, the time required for applying initial clearing when the AC power source is inputted to the power source device 21 is varied by adjusting the resistance value of a variable resistance 42, or varied by a variable resistance 37 when the circuit is turned off, and an initial clear signal 100 of a desired timing is generated.