Temperature measurement at a distance is often used in the control of industrial processes. For these purposes, it is recommended to use the infrared thermometers.
the design of the device and how it works
the Principle of operation of the pyrometer is to measure heat waves emitted from the heated surface. The General scheme of the pyrometer, if it is carefully considered, shows that the design of the device consists of:
- Optical system;
- Mirrors;
- Viewfinder;
on Its axis;
- Measuring and counting devices;
- Housing;
- Electronic Converter;
- Sensor;
- Buttons.
Radiation (heat energy) from the measurement object upon a sensor device, transformered into electricity. The higher the temperature of the surface, the greater the strength of the current generated by the sensor. Electronic Converter displays on the display the original temperature data.
the specifications
The IR pyrometer is a measuring device, so its work is characterized by different parameters, which is model selection. Consider some important parameters.
the
Optical resolution
It defines the area of the object, the temperature of the surface which should be measured. The greater the angle of the lens of the pyrometer (it depends on the optical resolution), the greater the area of temperature measurement. Also taken into account and the distance to the measured object.
The basic condition for precise measurement – overlay the spots on the surface material. If the area temperature is exceeded, the result will be inaccurate. The range of optical resolution depends on the instrument model and may be in the range of 2:1 (home device) – 600:1 (professional devices).
the
working range and accuracy
He revealed parameters of the pyrometric sensor. Most often, this range is-30C…+360) degrees Celsius. Error (on average) is allowed up to 2% of the normal readings. The most common thermometers model BALTECH TL-0208C temperature range (-50C to+800C and optical resolution of 50:1).
emissivity
Under the emissivity is the ratio (at current temperature) of two capacities: thermal radiation to the reference radiation of a blackbody (a blackbody). For most materials (not having a reflective and not a shiny surface) it is 0.9-0.95. But with so emissivity will not be able to accurately measure the surface temperature of shiny materials (e.g., aluminum). Obtained on the display, the result will differ from the actual values.
For more information about the device pyrometric equipment, the kinds and types of pyrometers, and pyrometric methods of surveys are invited to our technical seminars in Saint-Petersburg on the topic: “reliability Technologies” .