MONITORING DEVICE FOR PROGRAMMABLE CONTROLLER

A monitoring device for a programmable controller can resume continuous operation from an appropriate step, when the equipment is restarted after abnormality handling process. The monitoring device includes: a read device that reads operating state information of equipment from the programmable controller during individual operation; a relationship information storage device that stores relationship information showing relationship between the first step to be executed out of the steps when the equipment is restarted after the individual operation and the operating state information; a selection device that refers to the operating state information and selects the first step to be executed when the equipment is restarted, based on the relationship information; and a command transmission device that transmits a command to change an in-execution flag of the programmable controller which shows the first step to be executed when the equipment is restarted, based on the selection result of the selection device.