| 摘要 |
PURPOSE:To simplify the structure of a controller for a general operation of a motor by judging that a defect exists in a motor when an operation command signal of a motor is applied and no operation confirmation signal exists, thereby removing a relay for detecting the trouble in the controller. CONSTITUTION:A trouble discriminator 34 which is attached to a general controller 30 sequentially loads a start command signal of a master circuit 31 corresponding to a plurality of start controllers 20, and sequentially loads an operation confirmation signal of a motor 1 upon closing of a contact 26-a. When they are mutually abutted and no operation confirmation signal exists even if a start command signal is applied, it is judged that an overcurrent is flowed through the motor 1. In other words, it is judged that the operation relay 26 is deenergized by the opening of a thermal relay 13 due to the overload. Accordingly, an operation command signal is erased by an AND circuit 33 which inputs an overload detect signal, an operation command relay 21 is deenergized, and the motor 1 is stopped. |
