PURPOSE: To reduce the load of a host computer and also to facilitate the change of the result calculating method by providing a large display panel which is directly connected to a production control terminal equipment and can display the numerical value.

CONSTITUTION: A host computer 4 transfers the working contents of each process and the date on the number of targets, etc., to each production control terminal equipment PT 3 through a communication network 5. The PT 3 converts the received data into the display data for a large display panel 10 and displays the display date on a screen 10a. Then the PT 3 inputs the result data and sends this data to the computer 4. The PT 3 connected to the panel 10 stores its own data and also fetches only the necessary data from other PT 3 for calculation of the results. This calculating expression can be easily changed and set et a work site. The display data are produced based on the calculated data and displayed on the screen 10a. Thus the computer 4 is not required to produce the display data and therefore can reduce its load. Then the computer 4 can carry out other processing operations.