Temperature measuring position for electrical measurements

To investigate complex properties of material, measurements must be performed in wide range of temperatures. It is important especially in measurements of gas and humidity. The impedance spectroscopy measuring position allowing us to performing measurements in wide range of temperatures was made. Heating and cooling was performed by Peltier module unit. Temperature was measured by PIC16F877A microcontroller based module and transmitted by RS232 to the PC. Power was supplied by Agilent E3632A power supply and controlled by IEEE488.2 interface. The temperature and power level was controlled by PC computer with our made software using Agilent VEE environment. Software, using PID algorithm, allow to heat up or cool down measured sample from -10 to 50 deg. C with accuracy of 0.5 deg. With this position it was possible to control large dimension samples. Usable volume of the position was about 0,3 dm³ allowing us to perform automatic impedance spectroscopy measurements in preprogrammed temperature steps of large samples. Using of such position allow to reveal several physical phenomena unobservable in room temperature.