Hach Polymetron, User Manual, Page: 16 / 144

Troubleshooting
Intermittent data
During calibration, data is not sent to the datalog. Thus, the datalog can
have areas where the data is intermittent.
Test the conductivity sensor
If a calibration fails, first complete the maintenance procedures in
Maintenance on page 15.
1. Disconnect the sensor wires.
2. Use an ohmmeter to test the resistance between the sensor wires as
shown in
Table 4 .
Note: Be sure that the ohmmeter is set to its highest range for all infinite (open
circuit) resistance readings.
Table 4 Conductivity resistance measurements
Measurement points Resistance
Between blue and white wires 1089–1106 ohms at 23–27 °C
Between red wire and sensor body Less than 5 ohms
Between black wire and inner electrode Less than 5 ohms
Between black and red wires Infinite (open circuit)
Between black and white wires Infinite (open circuit)
Between red and white wires Infinite (open circuit)
Between red and inner shield wires Infinite (open circuit)
Between black and inner shield wires Infinite (open circuit)
Between white and inner shield wires Infinite (open circuit)
Between outer and inner shield wires Infinite (open circuit)
If one or more of the measurements is incorrect, call technical support.
Supply technical support with the serial number of the sensor and the
resistance values measured.
Sensor diagnostic and test menu
The sensor diagnostic and test menu shows current and historical
information about the instrument. Refer to
Table 5 . To access the sensor
diagnostic and test menu, push the MENU key and select Sensor Setup,
[Select Sensor], DIAG/TEST.
Table 5 Sensor DIAG/TEST menu
Option Description
SENSOR INFORMATION Shows the name and serial number that was entered
by the user.
CARD INFORMATION Shows the version and the serial number for the
sensor module.
CAL DAYS Shows the number of days since the last calibration.
CAL HISTORY Shows a list of the calibrations and the details for
each calibration.
RESET CAL HISTORY Service use only. Resets the calibration history for
the sensor. All previous calibration data is lost.
SENSOR SIGNALS Shows the current sensor signal and span in µS/cm.
SENSOR DAYS Shows the number of days that the sensor has been
in operation.
RESET SENSOR DAYS Resets the Sensor Days counter.
Error list
When an error occurs, the reading on the measurement screen flashes
and all outputs are held when specified in the controller menu. To show
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