Implementation of digital temperature system in research reactors using micro controller

Temperature transmitter is one of the most important transmitters in the reactor. It is used for resistance temperature detector (RTD) signal conditioning. It has built-in current excitation, instrumentation amplifier, linearization and current output circuitry which amplifies the RTD signal and gives linearization to it .It is a part of a system to get temperature and monitor it .This system is costly ,old and very complicated. In this work a digital system was implemented by using micro controller techniques which replaced the existing system.this replacement is the best because one chip (PIC16f877A) was used to build a digital system, which is more accurate and gave more performance and low costs.RTD is the sensing element of temperature, PIC (peripheral interface controller) micro controller was used for interfacing the transmitter, its built-in A/D converter was used and its EEPROM in this work,the PIC was programmed by using (C) language, mikro-C compiler and PROTEUS for designing the circuit and simulating it .The temperature was read, displayed on LCD, stored the upper limit ,lower limit in the EEPROM of the micro controller, calibrated the reading of A/D converter and gave alarm if temperature is greater than or less than this limit.