A four-point constant-current/temperature controlled circuit for anemometric applications

A four-point constant-current/temperature controlled circuit is an electronic system for supplying a resistance measuring sensor in two modes of operation: either in constant-current or in constant-temperature mode. This circuit is destined for anemometric applications. It is new nonbridge, four-point constant-current/temperature anemometer circuit. Separation of current and voltage leads of the sensor makes it possible to eliminate the effects of leads’ resistance on the preset value of sensor supply parameters. In such a circuit no cable adjustment is required. The value of sensor current or its resistance is set with digital signals. This article presents the design of the original measuring circuit and its principle of operation. Design of measuring circuit based on those principles is also presented. Attention is also given to its applications. The most important advantages of the new circuit are: both constant-current or constant-temperature modes of operation are available, precise digital control ...