JUMO 202580, Руководство по установке

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18 Technical data
18.2.6 Measuring circuit monitoring, optional boards
Input/Sensor Underrange/
overrange Short circuit/
sensor break Open circuit Special fea-
tures
pH-value (glass elec-
trode) Yes Configurable
Impedance mea-
surement
a
a
With impedance monitoring and detection of deposits, the sensor alarm is tripped in case of a fault.
Monitoring via impedance measurement can also be activated.
The following points should be observed to ensure correct function:
Impedance measurements are possible only with glass-based sensors.
Sensors must be connected directly to an analysis input for pH/Redox/NH
3
on the device.
Impedance converters must not be installed in the measuring circuit.
The maximal admissible cable length between sensor and device is 10 m.
Liquid resistance has a direct impact on the measurement result. It is therefore advisable to activate the im-
pedance measurement in liquids at a minimum conductivity of approx. 100 µS/cm.
Configurable
Impedance mea-
surement
a
-
pH-value (ISFET) Yes No
b
b
Errors in the measuring circuit (short circuit or line break) lead to display errors (underrange or overrange
or inadmissible value).
No
b
-
Resistive conductivity Yes No
b
Configurable Only with
4-wire circuit
a
Inductive conductivity Yes No
b
No
b
-
Universal input for con-
nection of: voltage/cur-
rent signal, RTD
temperature probe Yes No
b
No
b
-
Universal input for con-
nection of: resistance
potentiometer No
b
No
b
No
b
-