A programmable temperature control system

With the increasing complexity, manufacturing processes have become very sensitive to the physical parameters. Temperature control is one of the very important factor for them. In several processes the temperature of one unit needs strict regulation according to the temperature of some other unit. Potential applications exist in chemical industries and glass manufacturing industries. Generally, the relationship between the regulated unit temperature and the controlling unit temperature is non-linear. Thermistors are used as the temperature sensors since they are very sensitive to the small changes in temperature. The authors prove that the variation of their resistance with temperature can be made linear by connecting another resistor in parallel. The flexibility of programming any curve into the temperature control without changing the basic circuitry makes the designed control system useful in several industrial applications