Instruction manual
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You will now be prompted to type in the value of the buffer being used. Do so, then click
“Continue”.
You will now see the mV output from the electrode. When this value is stable, click “Continue”.
The WEBMASTER will either pass or fail the calibration, and prompt you to return the electrode
to the process. Click “Continue” when you are ready for pH control to resume.
If the calibration fails for any reason, refer to Section 8 for troubleshooting help.
1 Point Process Calibration
The new window will display the current value of the pH, using the last calibration. Measure the
pH of a sample of the water using a handheld meter, and type the new pH value in the text box.
Click the “Continue” button.
The WEBMASTER will either pass or fail the calibration. Control of the pH will continue
throughout this process.
If the calibration fails for any reason, refer to Section 8 for troubleshooting help.
Status
Possible status messages are; Normal (everything is OK), Sensor Error (the signal is not valid),
High Alarm, Low Alarm, Circuit Board Failure or Calibration Time. See section 8.1 for a
complete description of error messages.
Date of Last Calibration
This section is for information only, and lets you know when the last calibration occurred.
Calibration Reminder
If you want to be reminded when the sensor needs calibration, for example every 30 days then type
the desired number of days between calibration in the text box. A value of zero means you will
never be reminded. The highest value allowed is 365 days.
Uncalibrated mV
Displays the mV signal from the pH electrode in the current sample. This is useful for
troubleshooting.
Slope
This displays the slope (change in the mV output of the pH electrode per pH unit) of the pH
electrode as of the last calibration. A perfect electrode will change by approximately 59 mV per
pH unit. This is helpful for troubleshooting, and also to predict when the electrode may need to be
replaced.
Offset
This displays the mV output of the pH electrode in pH 7 as of the last calibration. A perfect
electrode will generate 0 mV at pH 7. The offset information is also helpful for troubleshooting.