A medical devices manufacturer needed to improve their coating process. The devices were ferried into the coating room via a constant-speed conveyer. They were presented vertically from 10 inches off the ground all the way up to 10 feet. In the coating room they needed to be precisely sprayed with a uniform coating. A pump spraying at 10 inches behaves differently when being sprayed at 10 feet. This change in spray added to multiple exhaust fans, warm-up cycles, and machine operators without the correct training equals an equation for Global Controls to solve.
The retrofit would need to control existing exhaust fans and the main conveyor. The servo system needed to vary the pump pressure and sprayer head speed according to altitude. The system also needed to store “recipes” for parts that are regularly produced.
For this application, Global Controls needed to combine multiple disciplines.
Motion Control: The servo-controlled belt drive had to be programmed to make precise vertical moves with user-selectable speeds at all positions. The spray head also had to be controlled by the servo system to control spray pressure. For this we chose the Parker Compax3 T30 servo controller. This controller offers world-standard IEC 61131 programming. It also has analog outputs to control the spray pressure.
PLC Control: The bulk of the machine required classic PLC-type control of I/O function, timers, speeds, and E-stop control. For this we utilized the extremely versatile WAGO-I/O-SYSTEM 750. The Wago system allowed for a complete and cost effective design. Slices of two, four, or eight points of discrete I/O (AC or DC), analog I/O, etc. were stacked together to meet our needs. The Wago also programs to the IEC 61131 standard. The analog output from the Wago allowed for speed control of all fans and the in-feed conveyor.
HMI Touchscreen: To pull the whole system together and allow for complete operator control we went with a Parker CTC Interact X touchscreen. The HMI communicated with both the Wago PLC and the Parker servo controller. This allowed for “recipes” that controlled servo speeds, positions, sprayer pressures, warm up timers, and I/O event triggers.
Panel Build: The true beauty of a complete Global Controls solution is the panel build. Our intimate knowledge of all the components and how they work together allow us to design panels that optimize each component. It also allows us to deliver to our customer a complete and tested system. This particular system was built, tested, and run-off by our customer in our Global Controls shop. Last minute change requests by the customer were quickly implemented before shipment. This process is an important benefit of Global Controls work as such changes are often very difficult in the field.