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Operating manual
1
1 General description.
The mixed-mode function is used to link two measured values of a ratio
pyrometer and to generate a continuous analogue output signal.
In the lower measuring range up to the start temperature of the transition
range, the measured value of the set source 1 is output.
Above the defined end temperature of the transition range, the output
signal corresponds to the measured value of source 2. A sliding transi-
tion takes place between the start and end temperature, in which the
measured values of the two sources are added together, weighted as a
percentage. The set controlling source determines the reference value of
the initial and final temperature of the transition range. In addition, the
entire measuring range of the mixed-mode channel can be set via the
parameters "Measuring range start" and "Measuring range end.
2 Mixed-mode function for extending the measuring
range
With mixed-mode operation, the measuring range can be extended to
lower initial temperatures by linking a spectral and a quotient tempera-
ture. At the beginning of the measuring range the device works as a
spectral pyrometer and from the end of the transition range as a ratio
pyrometer.
Since the pyrometer provides different measured values for the spectral
and quotient temperature depending on the emissivity of the measuring
object and the degree of partial filling of the measuring spot (if the
measuring object is smaller than the measuring field of the pyrometer),
the two measured values must be matched to each other in the middle of
the transition range for a linear transition.
For this purpose, the emissivity
ε1 or ε2 (depending on the selected
source) must be adjusted so that the two temperature values are identi-
cal in the middle.
Temperature
Persentage
partition
Controlling source
Measuring range Mixed mode
Transition region