Cell Constant - Hach 8311 Benutzerhandbuch

Contacting conductivity sensors: Use air (zero calibration) and the process sample to define the
calibration curve. When the process sample is used, the reference value must be determined with a
certified secondary verification instrument.
Inductive conductivity sensors: Use air (zero calibration) and a reference solution or process
sample to define the calibration curve. A reference solution calibration is recommended for best
accuracy. When the process sample is used, the reference value must be determined with a certified
secondary verification instrument.
Calibration limits
A calibration will fail if the value is ± 10% of the target value.

Cell constant

Before making a calibration make sure the sensor cell parameters are correct.
1. Push the menu key and select SENSOR SETUP>[Select Sensor]>CALIBRATE.
2. If the pass code is enabled in the security menu for the controller, enter the pass code.
3. Select CELL CONSTANT and push enter.
4. Contacting conductivity sensors: Select the cell K range for the sensor (0.01, 0.1 or 1.0) then
enter the actual K value as printed on the label attached to the sensor.
Inductive conductivity sensors: Enter the actual K value as printed on the label attached to the
sensor.
Zero calibration procedure
Use the zero calibration procedure to define the unique zero point of the sensor.
1. Remove the sensor from the process. Wipe with a clean towel to make sure the sensor is dry.
2. Push the menu key and select SENSOR SETUP>[Select Sensor]>CALIBRATE.
3. If the pass code is enabled in the security menu for the controller, enter the pass code.
4. Select ZERO CAL and push enter.
5. Select the option for the output signal during calibration:
Option Description
ACTIVE The instrument sends the current measured output value during the calibration procedure.
HOLD The sensor output value is held at the current measured value during the calibration procedure.
TRANSFER A preset output value is sent during calibration. Refer to the controller user manual to change
the preset value.
6. Place the sensor in air, push enter.
7. Review the calibration result:
• PASS—the sensor is calibrated and ready to measure samples.
• FAIL—the calibration is outside of accepted limits. Clean the sensor and retry. Refer to
Troubleshooting
8. If the calibration passed, push enter to continue.
9. If the option for operator ID is set to YES in the CAL OPTIONS menu, enter an operator ID. Refer
to Change calibration options
10. On the NEW SENSOR screen, select whether the sensor is new:
Option Description
YES The sensor was not calibrated previously with this controller. The days of operation and previous
calibration curves for the sensor are reset.
NO The sensor was calibrated previously with this controller.
on page 18 for more information.
on page 17.
English 13