Proxitron Piros OKSG L S18.194 S10, Руководство пользователя

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Block diagram current loop
internal resistance of connected devices
lead resistance
load resistance
resistivity
pipeline length (
conductor cross section
Example:
at 100 m cable length and approx. 15
Basics
Every real body emits according to its surface temperature infrared radiation which intensity is mostly less
than which of an ideal radiating black radiator of the same temperature. The ratio of the radiations is
characterized by emissivity ε. Emissivity charts can be found in citation /5/.
The pyrometer OKSG_L is specifically developed for industrial usage in the glass production for temperature
measurements from 600 °C on especially liquid glass. Glass is a transparent material so the radiation
predominantly comes from the volume of the glass. The visibility depth
of the pyrometer and accordingly
the maximum glass depth from whom the pyrometer receives the radiation is determined by the absorption of
the glass in the effective spectral range of the pyrometer. The absorption is heavily dependent from the
measurement temperature.
If the glass thickness is greater than
the transmissivity gets negligible; according to
Kirchhoff’s
laws the
emissivity results in:
The reflectivity ( of glass in the spectral range 0.5 µm to 8 µm is almost constant at 4 % to 5 %, so that for
glass the emissivity is 0.95 to 0.97. /7/
For low glass thickness (e.g. in glass feeder) the radiation comes more and more from the chamotte bed of
the glass trough. If glass drops of lower thickness are measured a lower emissivity has to be set.