Design of a Simple Temperature Transmitter Circuit of an Electric Heater Operated Water Bath

Temperature measurement and its transmission to a remote receiver are very important in any process plant, and various types of thermometer circuits are used for this purpose. In this paper, a simple temperature measurement and transmission system of an electric heater operated water bath is designed and studied experimentally without using any real thermometer. In this technique, electric heater current is taken as a temperature measuring parameter since the steady-state temperature of electric heater operated water bath depends on heater current only if we ignore a small variation of atmospheric temperature. The mathematical relations describing the operation of the proposed temperature measurement and transmission system are determined in this paper. The characteristic curves of the prototype unit of the proposed temperature transmitter are derived experimentally and are reported in this paper. The curves are found to follow the mathematical relations derived in this paper.