JPS5674709A - Function check method of sequence control device - Google Patents

Abstract

PURPOSE:To check the function in a state that the plant operation is continued, by providing a mock input storage part according to the mock operation at the time of checking the function, an input rewriting program, a temporary output storage part, and a transfer program, on the storage circuit, and executing the processing. CONSTITUTION:When the check command switch 51 is operated and the check command signal X is input to the sequence SQ control device 11 together with the external plant status input 16, the input rewriting program PG62 is operated, and the storage of an input 16 of the input storage part 31 is rewritten to the operation information corresponding to the check operation stored in advance in the mock input storage part 61. Subsequently, the device 11 executes SQPG32 in accordance with the contents of the storage part 31, which have been rewritten, and rewrites the contents of the temporary output storage part 62. After that, the SQ decision PG65 is operated, it is decided whether the contents of the storage part 63 coincide with the forecasting value of the storage part 61 or not, and before they coincide, only the address of the output storage part 33 corresponding to the check output Y is rewritten, the transfer PG64 is not executed, the contents of the storage part 63 are not transferred to the storage part 33, and the output to the external plant 18 is fixed before the check is started.