Hach Ultrapure pH/ORP Module Manuel D'utilisation page 11

1. Thoroughly rinse the clean sensor in deionized water.
2. Put the sensor in the reference solution. Make sure that the sensing area is fully immersed in the
solution. Stir the sensor to remove any bubbles.
3. Wait for the sensor and solution temperature to equalize. This can take 30 minutes or more if the
temperature difference between the process and reference solution is significant.
4. Push the menu key and select SENSOR SETUP>[Select Sensor]>CALIBRATE.
5. If the pass code is enabled in the security menu for the controller, enter the pass code.
6. Select the type of calibration:
Option
2 POINT
BUFFER
1 POINT
BUFFER
2 POINT
SAMPLE
1 POINT
SAMPLE
7. 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.
8. With the sensor in the reference solution, push enter.
9. Wait for the value to stabilize and push enter.
10. If the reference solution is a sample, measure the pH value with a secondary verification
instrument. Use the arrow keys to enter the measured value and push enter.
11. For a 2-point calibration:
a. Remove the sensor from the first solution and rinse in deionized water.
b. Put the sensor in the second reference solution and push enter.
c. Wait for the value to stabilize and push enter.
d. If the reference solution is a sample, measure the pH value with a secondary verification
instrument. Use the arrow keys to enter the measured value and push enter.
12. Review the calibration result:
• PASSED—the sensor is calibrated and ready to measure samples.
• FAILED—the calibration slope or offset is outside of accepted limits. Clean the sensor and
retry with a fresh reference solution. Refer to
information.
13. If the calibration passed, push enter to continue.
14. If the option for operator ID is set to YES in the CAL OPTIONS menu, enter an operator ID. Refer
to Change calibration options
Description
Use 2 buffers for calibration (recommended method), for example pH 7 and pH 4. The
buffers must be from the buffer set that is specified in the CAL OPTIONS menu (refer to
Change calibration options
Use 1 buffer for calibration, for example pH 7. The buffer must be from the buffer set that
is specified in the CAL OPTIONS menu (refer to
on page 14).
Use 2 samples of known pH value for calibration. Determine the pH value of samples
with a different instrument.
Use 1 sample of known pH value for calibration. Determine the pH value of sample with a
different instrument.
on page 14.
on page 14).
Change calibration options
Troubleshooting on page 15 for more
English 11