Temperature Measurement of Coal Pipe of Coal Mills by a Modified Bridge Circuit

Abstract

In our earlier work we proposed a method to measure the temperature of the coal pipe of Coal Mills in PF Boiler by a continuous basis, In order to achieve, accurate measurements of coal pipe temperature, using the resistive transducers like resistance temperature detector (RTD), the small resistance changes linearly with temperature, but resistance measurement by using RTD using normal Wheatstone bridge circuit would have errors for the stray capacitance presents in between bridge nodal points and the ground. Hence, by the use of a modified operational amplifier based Wheatstone bridge network, these effects can be minimized. The bridge performance has been studied experimentally with RTD. It has been observed good linearity, repeatability and variable sensitivity over the wide range of temperature.