
10
A) Emissivity settings : The emissivity can be set by clicking on
"Parameters” and select or type in the desired emissivity directly in
the description field. The emissivity value will be transferred to
pyrometer by hitting the "TAB" button. The emissivity range is from
0.1 to 1.0.
For a correct measurement it is necessary to adjust the emissivity.
This emissivity is the relationship between the emission of an real
object and the emission of a black body radiation source at the same
temperature. Different materials have different emissivities ranging
between 0% and 100%. The major parameters effecting emissivity
are:
1. The surface condition of the material,Rough surfaces have higher
emissivities.
2. The spectral range of the pyrometer and the measuring
temperature.
3. The Pyrometer spot size is fully filled by measured object or not.
4. The optical losses due to any obstraction in between pyrometer &
measured object like glass window.
A. 4.2.2Parameter Setting
All user selectable device parameters can be set by using the software in the Panel "Parameter".
The emissivity setting of the pyrometer has to be adjusted accordingly. The tolerance of the emissivity values for
each material is mainly dependent on the surface conditions.
(B)Unit : User can change the measuring unit of temperature from “Centigrade" to “Fahrenheit" and vice versa.
(C)Clear time (tCL) : if the peak picker is
switched on, the highest last temperature
value will always be displayed and stored. As
such, it may be beneficial to periodically clear
and reset the stored values in order to obtain
new temperature readings. This feature is
particularly useful when object temperature
is not uniform across its dimension or the
pyrometer is not constantly viewing an
object to be measured. The peak picker works
on two buffer memory to find maximum value
over a defined interval. With the first memory,
the highest measured value is held and is deleted alternately in the time interval set (clear time). The other memory
retains the maximum value throughout the next time interval. The disadvantages of fluctuations in the display with
the clock frequency are thereby eliminated.
Note: The maximum value storage coincides with adjustments made to response time. Therefore:
(I) Clear time<= the adjusted response time is useless
(ii) Clear times must be at least 5 times longer than the response time.
(iii) Only maximum with full maximum value can be recorded, which appear at least 5 times longer than response
time.
The following setting is possible:
OFF : At clear time “OFF” the maximum value storage is switched OFF and only momentary values are measured.
10msec...25sec : Any clear time between 10msec and 25sec (please refer to Note (ii) above) when set, estimates the
maximum values and holds it in two buffer memory. After the entered time, the storage will be deleted.