Cow Cement Sensor Based On Coil - Resistance Temperature Detector (C-RTD) Coupled with Four Wire Configuration Bridge (4-WCB)

Abstract

Low Temperature Detection System on cow cement flask base on RTD-coil coupled by transducer 4-WCB has been made. Four kinds of sensor was prepared, that's are coils from copper material with diameter 1 mm and set number of winding from 200 up to 500. Four-WCB circuit was chosen as transducer to facilitate the output voltage and to avoid the self heating on a wire directly connected with sensor. Liquid nitrogen is used as medium which its temperature will be measured. Temperature of medium was varied from -130 degrees C up to 0 degrees C. Collecting data was done on temperature and output voltage and output voltage was taken on each rising temperature of medium. Data temperature-voltage was analyzed by curve fitting according to quadratic polynomial y = ax(2)+ bx+ c. Sensitivity level of sensor was determined from slope of graphics, whereas the level of stability of sensor was determined from standard deviation. From plot of temperature -voltage data, it is known that all of sensors consistently tend to follow polynomial orde-2 form. It is found that sensor with the number of windings 400 is the most sensitive, but less stable compared with sensor 200 windings. Equation for potential (V) as function of temperature (T) concerning with sensor 400 windings is V = -0.00003T(2) + 0.32T + 77.09. This sensor has sensitivity and stability levels are 0,32 mV/degrees C and R-2 = 0,99 respectively.