MEDIUM TEMPERATURE MEASUREMENT DEVICE Russian patent published in 2014 - IPC G01K7/18 

FIELD: instrumentation.

SUBSTANCE: constant voltage source 1 is connected with its output to n-channel constant voltage switching unit 6 and shapes an interrogate current in a measurement circuit. Temperature transducers 41-4n and reference resistor 5 are connected in series so that a common electrical circuit is formed for passage of the interrogate current. The invention introduces (n+1)-channel switching unit 7 transmitting alternatively the information on drop of voltage on the temperature transducers and on the reference resistor at ADC 2. The information converted to a digital code is supplied to controller 3. Switching units 6 and 7 operate under control of controller 3 on the basis of software. The interrogate current is shaped in the form of periodic sequence of rectangular pulses with a relative duration, at which average current through a temperature transducer does not exceed an allowable value. As per the obtained resistance value of the temperature transducer, medium temperature is measured in the test medium.

EFFECT: higher measurement accuracy.

1 dwg