One-Point Calibration - bürkert 8201 Bedienungsanleitung

• The measured voltage is allocated to the pH value 2, 3 or 4.01 entered for the first buffer solu-
tion.
• Terminate the calibration mode on the measuring transmitter control menu.
• The sensor is calibrated for operation and can be installed in the connection fitting.
Recommendation: Check the two-point calibration after 1 to 2 weeks by means of a one-point
calibration using the process medium.

4.5.2 One-point calibration

The one-point or product calibration is used to check pH measurements and provide quality assurance
for the overall process. This calibration is based on an external single measurement of the pH value of
the process medium.
Implementation of one-point calibration
•
Take a sample of the process medium using appropriate equipment.
•
Ascertain the pH value of the medium sample via a manual device or in the laboratory.
• Read off the pH value for the process medium at the measuring transmitter.
• Compare the measured values and introduce the following measures depending on the differ-
ence.
♦ When measured values match
No need to take action
♦ When measured values differ slightly
Correct the reference value in the measuring transmitter as follows:
•
Activate the menu "one-point calibration" menu item of the measuring transmitter
•
Enter the new reference value of the externally measured pH into the control menu
•
Activate the calibration mode in the control menu. In this mode the voltage measured with
the sensor is allocated to the externally measured pH value.
•
Terminate the calibration mode on the measuring transmitter control menu.
♦ When measured values differ greatly
Check the overall pH measurement allocation and if required carry out a two-point calibration.
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