Evoqua WALLACE & TIERNAN SFC, Original Instruction Manual

Page: 204 / 288

204
WT.050.590.000.DE.IM.0719
Operation
SFC
6.
Measurement value calibration
(DPD)
10 After zero point calibration, wait at least 2 minutes.
11 Select the parameter "Cal. Span" and confirm with "Enter".
12 Open the input menu by pressing "Enter". The actual
measured sensor value is thereby cached and can be used for
later calibration. This is absolutely essential for fluctuating
measurement values.
13 Immediately after this extract specimen of sample water.
14 Determine the free chlorine, ozone, chlorine dioxide or
potassium permanganate content, for example, with a
photometer.
15 Use the arrow keys to enter the determined value. Finally save
by pressing "Enter". Should the measured sensor value (µA)
according to step 12 have changed, the measured value
displays another value immediately after calibration than that
which was entered in the calibration menu. This is based on
the change in the measured value during the calibration
process between step 12 and 15.
16 Press the soft key "back" several times until the main display is
shown. This concludes the calibration.
Please note
In the DPD calibration of the Cl
2
++ measurement the calibration
value should be greater or equal to 25 % of the measuring range.