Compact non-contact temperature measurement device for high-intensity microwave electromagnetic fields conditions

The practical implementation aspects of heated in microwave electromagnetic fields objects noncontact temperature measurement as one of the main factors in ensuring the quality of the heat-treated product are considered. The advantages of using the pyrometric method of temperature measurement in comparison with the thermocouple method under the influence of high-intensity electromagnetic fields are substantiated. A variant, which includes a cut-off waveguide with fasteners and a small-sized infrared sensor, for continuous temperature measurement system technical implementation of heated in a microwave field objects is proposed. The variants of proposed compact, cheap and versatile temperature measurement unit using a single-zone infrared sensor of the MLX90614 family, in application to conveyor microwave heating installations are described. The convenience of embedding the sensor into the microwave technological installation control system is noted due to the presence of programming functions for the emissivity of the measured object, the possibility of transmitting information about the object temperature using one of two digital protocols, as well as the possibility of building a network of several dozen measuring sensors on one two-wire digital data bus. The small size and weight, simplicity and relative cheapness of the contactless temperature measurement unit design allows it to be used in all types of microwave heating devices.

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