| 摘要 |
PURPOSE:To keep the mechanical life of auxiliary machines longer, by starting from an auxiliary machine with the shortest operation time and stopping an auxiliary machine with the longest operation time, in controlling process variables with a plurality of auxiliary machines. CONSTITUTION:A signal showing the operating state of auxiliary machines (motors)A,B and C is inputted to a comparison controller 8. An integration circuit 16 integrates each operation time of the auxiliary machines A, B and C. The operation times of respective auxiliary machiens are compared at a comparison circuit 17. It is assumed that the operation time of the auxiliary machine A is the shortest and that of the C is the longest. In case of one machine operation, the machine A is automatically selected and bronght to operation. If the machine A is infailure during the operation, the machine B which has the next shortest operation time is driven. When a stop instruction is given while the machines A, B and C are in operation, the machine C is stopped. The controls can be made by the output of the comparison circuit 17. |
