METHOD TO MEASURE MEDIUM TEMPERATURE Russian patent published in 2015 - IPC G01K7/18 

FIELD: instrumentation.

SUBSTANCE: method is proposed to measure medium temperature, according to which voltage drop is measured on a thermistor programmatically under management of a controller and on a reference resistor. The thermoelement and the reference resistor are connected in series to form a common electric circuit for passage of interrogate current. The platinum thermoelement of resistance is placed into an investigated medium. Interrogate current is generated as a periodical sequence of rectangular pulses with duty factor, in which average current via the thermoelement of resistance does not exceed the permissible value. The duty factor value is determined in accordance with the following formula: $$Q>\frac{Us}{(Rt+Rref)\times Iper},$$ where Q - required duty factor of pulse sequence, Us - value of DC voltage of the source of power supply that generates interrogate current of the thermoelement of resistance and reference resistor, Rt - value of thermoelement resistance at minimum measured temperature, Rref - rated value of resistance of the reference resistor, Iper - maximum permissible interrogate current of the thermoelement.

EFFECT: increased accuracy of temperature measurement.

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