Evoqua WALLACE & TIERNAN SFC SC, Original Manual

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WT.050.590.020.DE.IM.0719
Installation
SFC SC
5.
5.3.5 Positioner calibration
If you are using a positioner with feedback it is possible to linearize
the control output, for example if using a gas feeder which has a
positioner with feedback. Here, for example, 30 % control
(opening) does not equal 30 % dosing capacity. Calibration of the
positioner feedback allows up to eleven dosing capacity points to
be aligned, in order to obtain dosing that is as linear as possible.
For this purpose, the number of support points to be calibrated can
be selected in the „Dosing“ menu - „Ym Calib.Points“. It is possible
to calibrate 2, 3, 6 or 11 support points. The more support points
are selected, the more accurate is the dosing.
• Starting from the basic display, select the „Dosing“ menu.
• In the „Ym Calib.Points“ menu, select the number of
calibration support points.
• Select the „Act.Calibration.Man“ menu and confirm with the
Enter key.
• The dosing outputs to be calibrated are shown on the display
(max. 11).
• The calibration points can be selected using the up/down
arrow keys. Press Enter to calibrate the support points, and
use the up/down arrow keys to open/close the positioner until
the actual dosing shown on the dosing capacity indicator (e.g.
gas feed inspection glass) agrees with the calibration point
(e.g. 20%). Save the value by pressing the Enter key.
• Select the next calibration point and align the actuator position
as described.
Please note
All calibration points must be aligned or checked in order to obtain
linear dosing output.
000% 0.0 (calibration point 0 % dosing)
020% 20.0 (calibration point 20 % dosing)
040% 40.0 (calibration point 40 % dosing)
060% 60.0 (calibration point 60 % dosing)
080% 80.0 (calibration point 80 % dosing)
100% 100.0 (calibration point 100 % dosing)