Instruments and Systems: Monitoring, Control, and Diagnostics Annotation << Back Microprocessor system of automatic control of a thermal conditions of technological process of cultivation of a crystal of sapphire A.S. KIZHUK YU.A. GOL’TSOV By analyzing of temperature control system of unit for sapphire crystal growing, applied in production, are revealed significant disadvantages, affecting both the quality of the process and energy consumption in manufacturing. Here is proposed a structure of microprocessor automatic control system and software of its functioning, eliminating revealed lacks, associated with phase imbalance of supply voltage and appearance of higher harmonics, negatively affecting industrial voltage supply quality. Providing technological modes of heating installation carried out using the power supply circuit of two groups of field-effect transistors, operating in dynamic mode with minimum drain-source resistance at the time of switching, which required the development of control system on a monostable multivibrator. To implement regulating laws are used modern microcontroller tools and technological programming languages, recommended by the IEC. Usage of visualization tools enables graphical representation of current information, operational control and corrective parameters, as well as notification of emergency modes. Also here is shown efficiency of system operation, using PID control law with width modulation and proposed specific technological solutions. Keywords: crystals growing, crucible, heater, temperature, control, thyristor regulator, field effect transistor, structure, program, control law, algorithm Contacts: E-mail: kizhuka@mail.ru Pp. 42-49.