An apparatus for discriminating between liquids having differing thermal conductivities includes a thermally conductive substrate, a resistor and a thermistor mounted to the thermally conductive substrate. Two leads on the resistor enable a current to be passed through the resistor to generate heat, and two leads on the thermistor enable a current to be passed through the thermistor to generate a datum indicative of thermistor temperature. An electrical insulator encapsulates the resistor, the thermistor and part of the thermally conductive substrate. A remainder of the thermally conductive substrate may extend beyond the electrical insulator to provide a thermal path from the resistor and thermistor to a liquid in which the apparatus may be immersed.
展开▼
