1. 4-channels high temperature meter
2. Thermoprobe structure
3. Thermoprobes range
4. 4-channels high temperature meter Flow chart
5. Front panel and touch screen
1 - 'power' button, 2 - on/off/switch input of display, 3 - adjusting of the backlight brightness, 4 – SD memory card slot, 5 - USB socket
6. Rear panel. Plugging chart


The device is designed to measure the temperature of heated medium by contact method using submersible thermoprobes. These sensors are engineered and manufactured on the base of commercially available Ceramic Thermocouple Protective Tubes. The principle of operation is as follows - optical system of the device collects light irradiation from the bottom of protective tube, transfers it by fiber optics to MEMS-based multichannel optical switch and then into a spectrophotometer. The temperature is defined as a parameter of the detected spectral distribution in visible/near-infrared range by direct fitting the data of the spectrophotometer to Planck's law. 
Such method of temperature measurement practically eliminates the influence of powerful electromagnetic fields on the temperature readings and allows measuring it where thermocouples fail or the accuracy of their data is questionable (into microwave, induction or arc furnaces, heaters under high electric potential, etc.). Lifetime of the thermal probe is determined by thermochemical/mechanical resistance of the protective tube material only. The proposed high temperature meter combines the advantages of classical contact (thermocouple) and optical (pyrometry) methods for high temperature measuring, contains x86 computer and can be easily integrated to the industrial control systems.

Main specification of 4-channels high temperature meter (experimental model)

Name Value Note

Channels number 4 Channels number is caused by using 4-channel compact optical switch fabricated by MEMS technology. May be equipped by 2, 4, 8, 13, 16, and 24-channel optical switch.

Temperature range, °С 600 - 1950 Lower limit is due to the use of relatively inexpensive optical components and the upper - permissible temperature of commercially available thermocouple protective tubes. Measurement of temperature above 1950°C is possible applying a special protective tube.

Accuracy, % 0.5 or better

Calibration interval one year
Thermoprobe dimensions: working part external diameter, mm working part length, mm 3-19

Control Unit: dimensions, mm weight, kg 225x180x112 2.2

Length of connecting fiber optic cables, m 5 There is possible to increase the cables length to 100 m and more