DEVICE MEASURING CONDUCTIVITY Russian patent published in 2002 - IPC

FIELD: instrumentation used in aviation and metallurgical industries and mechanical engineering to test quality of current-conducting articles by value of conductivity of their materials. SUBSTANCE: device measuring conductivity has self-excited oscillator and eddy-current converter connected in series, phase detector which input of reference voltage is connected to self-excited oscillator, indicator, compensator and adder connected in series. Second input of adder is connected to eddy-current converter and output of it is coupled to input of phase detector. Input of compensator is connected to self-excited oscillator. Device also incorporates temperature measuring unit, switch which second input being connected to output of phase detector, analog-to-digital converter, controller and indication unit connected in series. Controlling inputs of switch and analog-to-digital converter are connected to proper outputs of controller. Device in addition includes calibrator made up of two current-conducting plates with known temperature coefficients of conductivity and values of conductivity close to upper and lower measurement limits of device. EFFECT: raised reliability of non-destructive test of properties of materials and articles by their conductivity. 2 cl, 1 dwg