Evoqua WALLACE & TIERNAN 700 P, Инструкция по эксплуатации

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700 P electronics module
Operation
6.
123
DPD ? Slope error
The current difference required for
span alignment over the entire mea-
surement range was less than the
minimum value.
Range: Minimum current difference
10 µA 0.04 µA/mg/l
100 µA 0.4 µA/mg/l
1000 µA
4.0 µA/mg/l
Check Cl
2
sensor.
Clean electrodes.
Check the pH value of the water
(< pH 8).
Organic chlorine compounds (e. g.
high concentration of chlorine
stabilizer chloroisocyanurate) in the
water. Do not add high concentrations
(<30 mg/l) of chlorine stabilizers to
the water.
Incorrect Upot for CL
2
sensor. Set Upot: 250 mV, see page 70.
Calibration pH7 ?
Calibration pHX ?
Calibration ?
Offset calibration ? 3-electrode measuring cells or mem-
brane sensors:
Slope error - the sensor current
based on 1 mg/l has fallen below the
required minimum. Check whether there are air bubbles
on the membrane sensor and
remove, if necessary.
Service membrane sensors -
replace electrolyte/membrane cap.
Clean 3-electrode measuring cells,
replace cleaning sand.
pH:
In pH 7 calibration, the sensor signal
is outside -100 to +100 mV or the
sensor issues a signal outside 46 to
70 mV per pH increment, the cali-
bration point distance is smaller than
1 pH increment. Check the electrode.
Check the buffer solutions, replace if
necessary.
mV:
The mV electrode correction offset is
outside -50 to +50 mV. Check the electrode.
Check the calibration solution,
replace if necessary.
Conductivity:
Conductivity measurement spread
is smaller than 0.8 or larger than 1.2. Clean the sensor, check it and if
necessary, replace it.
Measuring cell ?
Calibration of factory ? Hardware or electronics fault Contact Service.
Setpoint ? Due to modification of the measure-
ment range, the controller setpoint is
outside the measuring range. Reset the controller setpoint or
adjust the measurement range.
Error message Cause Remedy