40
6 Set up with the display and adjustment module
MINITRAC 31 • Foundation Fieldbus
41782-EN-211203
L
Fig. 21: With inclined mounting, the radiated length of the tube is applicable
In this menu item you can carry out the adjustment of the sensor.
Caution:
During the first setup or after an instrument reset, the linearization
stands at the preset value pair (90000 ct/s and 0.500 g/cm
3
). These
values are not suitable for your application and must be replaced by
real values. Delete this value pair in the following procedure and carry
out the linearization.
Due to the measuring principle, there is no linear relationship between
pulse rate and density. Hence, this adjustment (i.e. linearization) must
be carried out in any event.
Carry out this adjustment with several points to increase the accuracy
of the measurement.
Note:
Water has as a known density value of 1 g/cm
3
. Carry out the adjust-
ment with water, if possible.
•
Prerequisites:
Radiation is switched on - Source container is set to "ON"
The tube is completely filled. Possible gas bubbles or air inclusions
can influence the measurement.
The MINITRAC 31 sorts the points automatically according to their
density.
Linearisation
