Wheatstone bridge, use

One Form of the Wheatstone Bridge Used with the Electrical Conductivity Detector... 

The most typical electrical circuits for control and evaluation of a thermoresistive flow sensor are based on the well-known Wheatstone bridge using either the constant-current or the constant-temperature mode, respectively [4]. In a constant-current circuit (see Fig. la), resistors R and R4 at the two arms are much larger than the sensor... 

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