Commissioning
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optek-Manual--1004-1022-02--156-US-2017-12-11
Proceed as follows to set the variable measuring range:
1. Fill the armature with a slightly hazy liquid or dip the probe into a slightly hazy
liquid. You may as well cover the light beam - if the sensor assembly is not
yet installed - so that a stable measuring result is obtained within the set
measuring range. This fixed measuring range should be selected providing
that the desired variable measuring range is included in this fixed measuring
range.
2. Connect a multimeter to terminals 8 and 9 on the back of the converter.
It displays the corresponding measuring result in mA.
3. Use a screw driver to set the desired variable measuring range at the
potentiometer (11) turning. Proceed according to this example:
•
Preset measuring range:
0 - 3.0 CU
mA display (4 - 20): 12 mA
corresponds to measuring result:
1.5 CU
•
Switch to variable measuring range.
•
Variable measuring range:
0 - 2.3 CU (desired)
•
Turn the potentiometer (11) to the right (or left), until the following indi-
cation appears for the mA-output:
mA display (4 - 20): 14.4 mAcorresponds to measuring result: 1.5 CU
•
Check zero point (see chapter 9.4, page 31).
Adjustment value calculation:
Note!
The dynamic measuring range of sensors with color-sensitive detector module
(AF56 or AS56 to 156 converter) may be reduced. Since optical filters consider-
ably reduce the wanted signal, normally only measurements of up to
2 CU are possible.
Fig. 22
Potentiometer for measuring range adjustment
measuring range (1.5 CU)
desired range (2.3 CU)
---------------------------------------------------------------------
16 mA
4 mA
+
×
14.4 mA
=
11
