Visualization and control of the multi-purpose vacuum hot table at the National Gallery Prague

In 1999, the PROTECO company implemented a system for the control of the multi-purpose vacuum hot table at the National Gallery in Prague. The vacuum hot table is a unique piece of technology. Its main function is to help when restoring paintings created on different kinds of canvas. First, a painting's canvas is fixed onto the perforated surface of the vacuum hot table through the process of suction. Heat, cool, suction control, and humidity control are then employed to influence the painting's surface.

All the above stated operations are continuously controlled according to predefined recipes. The recipes specify the course of individual process steps, i.e., required trends of individual controlled physical quantities. All data is logged to databases to be rechecked or displayed in trends. The hardware base includes a Tecomat TC606 PLC.

The vacuum hot table is completely controlled from the operator's personal computer. This computer is equipped with the Reliance SCADA/HMI system to control the restoration processes. Thanks to several well-arranged visualization windows created with the Reliance system, the gallery staff can fully control the painting restoration process itself. The chosen hardware solution (Tecomat PLC) and the Reliance system proved to be efficient in the restoration of paintings.

Example of a visualization window