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Option Description
TDS (total Note: The TDS (total dissolved solids) setting is only available when the Measurement type setting is set
to TDS.
dissolved solids)
Sets the factor that is used to convert conductivity to TDS—NaCl (default) or Custom
(enter a factor between 0.01 and 99.99 ppm/µS, default: 0.49 ppm/µS).
Cable parameters Sets the actual length of the sensor cable to improve measurement accuracy (default:
5 m).
Temperature Sets the temperature element for automatic temperature compensation to PT100 (default),
element PT1000 or Manual. If no element is used, set to Manual and set a value for temperature
compensation (default: 25 °C).
Note: If Temperature element is set to Manual and the sensor is replaced or the sensor days are reset,
Temperature element automatically changes back to the default setting (PT100).
Filter Sets a time constant to increase signal stability. The time constant calculates the average
value during a specified time—0 (no effect, default) to 200 seconds (average of signal
value for 200 seconds). The filter increases the time for the sensor signal to respond to
actual changes in the process.
Data logger interval Sets the time interval for sensor and temperature measurement storage in the data log—
5, 30 seconds, 1, 2, 5, 10, 15 (default), 30, 60 minutes.
Reset to default Sets the Settings menu to the factory default settings and resets the counters. All sensor
values information is lost.
4.3 Calibrate the sensor
Fluid pressure hazard. Removal of a sensor from a pressurized vessel can be dangerous. Reduce
the process pressure to below 7.25 psi (50 kPa) before removal. If this is not possible, use extreme
caution. Refer to the documentation supplied with the mounting hardware for more information.
Chemical exposure hazard. Obey laboratory safety procedures and wear all of the personal protective
equipment appropriate to the chemicals that are handled. Refer to the current safety data sheets
(MSDS/SDS) for safety protocols.
Chemical exposure hazard. Dispose of chemicals and wastes in accordance with local, regional and
national regulations.
4.3.1 About sensor calibration
The sensor characteristics slowly shift over time and cause the sensor to lose accuracy. The sensor
must be calibrated regularly to maintain accuracy. The calibration frequency varies with the
application and is best determined by experience.
Use air (zero calibration) and the process sample to define the calibration curve. When the process
sample is used, the conductivity of the process sample must be identified with a certified secondary
verification instrument.
During calibration, data is not sent to the datalog. Thus, the datalog can have areas where the data is
intermittent.
4.3.2 Calibration limits
A calibration will fail if the value is ± 10% of the target value.
4.3.3 Cell constant
Before a sensor calibration is done, make sure that the sensor cell parameters are correct as follows:
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