Compensation of Self-Heating in the Measurement of the Dynamic Response of a Thermoresistive Sensor

In the experimental determination of the response time of a thermoresistive sensor to a radiation step, one needs to monitor the variation of the ohmic resistance of the sensor with time. This requires passing electrical current through the sensor, which introduces error in the measured response time due to the additional self-heating of the sensor by the electrical current. A theoretical method to eliminate this error is formulated and experimental results are presented. The proposed method also permits experimental determination of the heat capacity (mc) and heat transfer coefficient (UA). The sensitivity analysis of τ = mc/UA permits the optimal choice for the resistance measurement currents.