Evoqua WALLACE & TIERNAN SFC, Оригинальное руководство пользователя

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WT.050.590.000.DE.IM.0719
Operation
SFC
6.
Calibration? In 3-electrode cells and membrane
sensors
Slope error - the sensor current
based on 1 mg/l has fallen below the
required minimum
In measuring range:
10µ : min. 0.04 µA/mg/l
70 µA: min. 0.2 µA/mg/l
100 µA: min. 0.4 µA/mg/l
200 µA: min. 2 µA/mg/l
1000 µA: min. 4 µA/mg/l
Check whether there are air bubbles on
the membrane sensor and remove, if
necessary
Service membrane sensors - replace
electrolyte/membrane cap
Clean 3-electrode cells, replace cell
sand
With pH
with pH 7 calibration, the
sensor signal is outside
-100 – +100 mV or the sensor
delivers a signal outside 46 – 70 mV
per pH step
the distance of the calibration point
is less than 1 pH step Checks electrode,
Check buffer solution,
Replace if necessary
With mV
the correction offset of the mV
electrode is outside -50 – +50 mV Check electrodes,
Check buffer solution,
Replace if necessary
Conductivity
measurement spread is smaller
than 0.8 or larger than 1.2 Clean sensor,
check,
change sensor if necessary
Fluoride
The rate of change of the sensor
curve is too small or the calibration
limits have been exceeded
0,2 mg/l: 40 – 160 mV
2.0 mg/l: -10 – 100 mV
20 mg/l: -60 – 40 mV
The lower cal. value sensor voltage
must be 20 mV higher than the
upper cal. value Check electrode, cable and standard
solution, use fresh standard solution,
replace electrodes
mA output? Load error
The mA output cannot drive its mA
output current through the
connected current loop (500 Ohm at
20 mA max.). Check whether the mA signal is
required at all (e.g. for plotter). If not, in
the "INPUTS/OUTPUTS" menu,
„analog output“, switch off the output
signal.
Check the mA signal cable for
interruption
Temperature ? Interruption in the
temperaturesensor or multi-sensor
cable Check multi-sensor and cable
Error message Cause Remedy