REPLACEMENT OF THE RELAY CONTROL SYSTEM IN AN OLD IMPORT WINDING TYPE VACUUN COATING EQUIPMENT WITH PROGRAMMABLE CONTROLLER

A method to replace the relay control system of an old import winding-type vacuum coating equipment with a programmable controller（PC） is introduced. A great deal of attention is paid to the choice of the PC model and the disposition of the related hardware. The method is also suitable to the control of home-made coating equipment.