Hach-Lange POLYMETRON 9500 Conductivity Module User Manual - Manual (Page 19)

Test the inductive conductivity sensor
If there is a doubt concerning the operation of the sensor, disconnect it from the controller but leave it
in place in your sample process. Check the following resistance values across the terminals indicated
(refer also to the wiring table
Table 1 on page 6):
Wiring connections Resistance
Terminals 7-10 (Temperature sensor Pt100) ≈ 110 Ω (at 25 °C)
Terminals 1-2 (Secondary coil) ≈ 1—2 Ω
Terminals 11-12 (Primary coil) ≈ 1—2 Ω
If the checks do not generate any erroneous resistance values, the sensor can be considered to be
working properly.
If the measurement is still not satisfactory proceed as follows:
1. Set T-COMPENSATION to NONE (see Inductive conductivity sensor configuration on page 10).
2. Perform a ZERO CALIBRATION of the sensor (see Zero calibration procedure on page 13).
3. Perform a RESISTOR CALIBRATION of the sensor (see Resistor calibration (inductive
conductivity sensors) on page 16).
4. Check the following:
Displayed conductivity (K = 2.35) Simulated resistance
470 μS/cm 5 kΩ
4.7 mS/cm 500 Ω
47 mS/cm 50 Ω
470 mS/cm 5 Ω
Sensor diagnostic and test menu
The sensor diagnostic and test menu shows current and historical information about the instrument.
Refer to
Table 2 .
To access the sensor diagnostic and test menu, push the menu key and select SENSOR
SETUP>[Select Sensor]>DIAG/TEST.
Table 2 Sensor DIAG/TEST menu
Option Description
MODULE INFORMATION Shows information about the sensor module.
SENSOR INFORMATION Shows the name and serial number that was entered
by the user.
CAL DAYS Shows the number of days since the last calibration.
CAL HISTORY Shows a list of all calibrations by date/time stamp. Use
the arrows keys to select a calibration and push enter
to view the details.
RESET CAL HISTORY Resets the calibration history for the sensor (requires
service-level passcode). All previous calibration data is
lost.
POLARIZATION Contacting conductivity sensors only. Shows
information about the electrode polarization, the cable
capacitance and the time before the next
measurement.
English 19