Diagnostic method for production line

摘要

A diagnostic method for a production line. The production line is in accordance with a ladder program, which is prepared on the basis of a map describing the operations of equipment composed of a plurality of drive devices. The method comprises the steps of: storing reference operation times necessary for executing the respective operations of the program elements of the ladder program; comparing the time it has actually taken a change to take place in the ON/OFF condition of each of confirmation devices for confirming the operations of the drive devices with the corresponding reference operation time; and locating, on the basis of the results of this comparison, any malfunctioning point of the production line.