Resistance Measurement
To measure the resistance of the temperature detector, a current must be passed through the device - typically a current 1mA to 5mA. A source current of 1mA flowing through the 100Ω resistance will generate 100μW of heat. If the sensor element is unable to dissipate this heat it will indicate an artificially high temperature.This effect can be minimised by using a large sensor element that is in good thermal contact with its measurement environment, while allowing sufficient time for the temperature to stabilise. An alternative is to use a short measurement pulse of current thus minimising the heating effect. A good thermometer may be configured to measure with either a continuous or a short current pulse ensuring that the best possible measurement is made.
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