the Color of the photovoltaic devices or pyrometers of spectral relation is intended for automated measuring temperature in different industrial sectors (e.g. energy, metallurgy, petrochemicals) and in the practice of scientific research.
Such pyrometers (thermometers) is based on the temperature dependence of the subject of the relationship of the spectral energy brightness in 2 spectral regions with specific values of the effective wavelengths. The pyrometer can be performed in single channel (one receiver two spectral brightness alternately act) scheme or a two-channel (separate receiver for each spectral brightness).
single-channel devices
In the single-channel devices of two different monochromatic energy flux is alternately fed to one of the photoelectric receiver through the disk shutter or an optical switch. In their holes are the appropriate filters (blue and red). If the requirements for the consistency of the schematic elements are reduced, the measuring principle is able to improve the stability characteristics of the thermometers. Therefore, more and more are made the pyrometers of spectral relation at the single-channel scheme.
Dual device
The scheme of two-channel device has a disk obturator (used to modulate the flow of energy rays). The light modulator provides the opportunity to use stable amps AC current, but the instability of photovoltaic cells is the source of errors.
Advantages of pyrometers of spectral relation
For both receivers of the measuring device have the same dependence of signal on distance. Therefore, this dependence does not affect the ratio of the signals. On the ratio of signals from two receivers (it remains unchanged) have the same effect:
- Fumes in a staging environment;
- Dust;
- Shape of the measured object.
The spectral relations are insensitive to:
- protective glass;
- the Presence of small opaque objects located in the field of view of the measuring device;
- Side flashes from objects with large sizes.
Disadvantages of pyrometers of spectral relation
disadvantages of such thermometers include:
- the Cost of the device. The spectral pyrometer relationship consists of many elements and harder calibrated. So they are expensive. You have to pay for additional nodes and additional work;
- Influence of the emissivity of the object on measurement results. With the increase in wavelength decreases the spectral emissivity. Therefore, the long-wave signal receiver of the pyrometer will be lower compared to the short-wave device). Therefore, the readings of the device are inflated by 10% or more.
For temperature control of electrical equipment in hidden areas (e.g. electrical cabinets), we recommend the use of infrared glass BALTECH TR-75W.
For more information on comparative characteristics of thermometers and thermal imaging cameras you can find in our licensed training centre in the course TOR-104.