| 摘要 |
PURPOSE:To easily set a suitable current detecting level of an induction motor by monitoring the operation of a current detecting acceleration completion discriminator circuit directly by a display circuit. CONSTITUTION:An output terminal d having the same potential as the output terminal c to a phase control circuit for a rectifier connected in antiparallel with the phase S of a motor is newly provided in a current detection acceleration completion discriminator circuit 8, and a resistor 9 as well as the base and the emitter of a transistor 12 are connected between the terminal d and the input terminal b of the input terminals a, b of a T-phase current. A resistor 10 and a photodiode 11 are connected in series between the collector of the transistor 12 and a positive DC power supply terminal VDD. Since the circuit 8 produces an acceleration completion signal to the terminals c, d when the current level becomes lower than a predetermined level, the photodiode 11 is turned off. In this manner, the current detecting level of the circuit 8 can be monitored directly, thereby, the current detecting level can be easily set. |
