PLC controlled cascaded water tank system

This project demonstrates the extensive application of the Siemens S5-95U Programmable Logic Controller. It utilises almost all the features of a good programmable controller now available in the market. The PLC's most notable feature, the handling of analog input and output data is actually the main feature of this project. The water tank system is composed of 3 tank systems connected in cascade series. Tank 1 is used for cold water storage, and tank 2 is the one used in the process. An interface module was created that displays the system different parameters. These are the tank's temperature and level. The interface is a stand-alone module which only requires power and the systems inputs. The module displays the system's current reading through an LED bar graph. The system setpoints can all be adjusted on the module. The controller generates a digital control bit depending on the desired system operation. This programmable controller and interface module work in conjunction with the existing water tank system found in the control laboratory.