MICRO-EPSILON capaNCDT 6500, Инструкция по эксплуатации, Страница: 30 / 68

capaNCDT 6500 Page 30
Operation
Step 2: Linearity
The measured value differences B-A and C-B are calculated from the fixed measuring
points A B C and compared with each other. The setting of the linearity potentiometer is
now altered until B-A and C-B are identical.
If the setting is not valid, you can do the following:
Add with the trimmer “Lin“ a quadratic component to the signal, which compensates
the physical not linear characteristic of insulators.
If the value C exceeds 10 V the sensitivity (“Gain“) must be reduced.
If the “Lin“ potentiometer is at the stop and B-A and C-B are still not equal, points A and
C have probably been badly chosen. Start again with step 1.
Step 3: Sensitivity
In order to set a practicable sensitivity, first form the signal difference C-A and select a
sensitivity which matches the measuring range (for example 1 V/mm). Set the distance
point C and calculate the required measured value C’.
C´= C
E
(C - A)
E ... desired signal span point A to C
C ... signal value at distance point C
A ... signal value at distance point A
If C’ is not more than 10 V, set it with the “gain“ potentiometer.
As a final check, run through the whole measuring curve and document it.
Step 4: Zero point
Finally the electrical zero point can now be shifted with the trim-pot “Zero“ without affect-
ing the linearity and sensitivity.
3
2
1
Sensor
Target
Signal
0
1
0.5 Measuring
range 1
Fig. 29 Signal behavior of the output voltage
Advice for digital interface
Zero point shifting, option of digital linearization, possible by software.
Please take details, see Chap. 6.
If the measuring values were selected digitally, the analog and digital measuring values
disagree after a zero point shifting with the zero-poti.