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temperature is most studied in terms of metrology, it is
practically useful to measure it instead of directly measuring a
number of characteristics of an object depending on its state
and of immediate interest to the technologist. Such
characteristics include the energy of a substance, its chemical
activity, viscosity, hardness, changes in its chemical or phase
equilibrium, the rate of change in structure, thermal expansion,
changes in electrical and magnetic properties, etc.
At the same time, temperature measurement by contact
methods with the help of thermometers has inherent difficulties
that increase sharply with increasing temperature. These
difficulties are associated with the choice of material for the
sensor, which would ensure the stability of the readings and
minimal impact on the object of measurement, with the choice
of insulation materials for thermometers. The errors associated
with contact measurements with imperfect thermal equilibrium
between the thermometer and the object, with poor thermal
contact and extraneous thermal influences can be significant.
Temperature measurement by thermal radiation makes it
possible to circumvent these difficulties, since there is no direct
effect of temperature on the materials of the device, and the
measurement itself is carried out without contact.
A device for measuring temperature at remote points is
intended for contactless measurement of the temperature of
objects at a distance of several meters from the sensor. The
basis of this device is a pyrometric sensor, which converts the
thermal radiation of an object, which is electromagnetic waves
of various lengths, into an electrical voltage. Thus, the device
in question should provide for converting the voltage from the
sensor output to the corresponding temperature value and
display it on the indicator. The dependence of the output
voltage on the M18TUP14Q sensor on the object temperature
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has a linearity in the range of 0 ... 50ºC and 1 in the range of 50
... 300 ºC.
From the output of the pyroelectric sensor, the voltage
goes to a low-pass filter (LPF), from the output of which the
signal goes to an attenuator, through which the device is
calibrated by changing the transfer coefficient. Next, the signal
arrives at the matching device (SU) designed to connect the
sensor to the ADC. From the output of the ADC signal is fed to
the input of the microcontroller (CPU1). The microcontroller
recalculates the code corresponding to the output voltage of the
sensor to the temperature of the object.
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