STANDARD OPERATING PROCEDURE Title: pH Calibration

1. PURPOSE

It is established for the calibration of pH meter.
2. SCOPE
It is applicable to Quality Control Department.
3. RESPONSIBILITY:
1. Quality Control Manager
2. Assistant Manager Quality Control
4. PROCEDUR
pH CALIBRATION for H19318 PROCEDURE.
• Switch the instrument on after the electrode and temperature probe.
• Immerse the pH electrode and the ATC probe into pH 7.01 buffer solution.Shake briefly and wait 1-2 minutes for thermal equilibrium.
Note: The electrode should be submerged approximately 4 cm (11/2) into the solution.The temperature probe should be positioned as close to the pH electrode as possible.
Press the CAL key.

The Printer will then print step by step instructions for the
Calibration procedure.

At the same time the pH symbol will flash to indicate that calibration is in progress.The ph value at the measured (or manually) adjusted temperature will be displayed.
If “Err 4” appears on the display it means the electrode is in the wrong buffer.Check to make sure that the electrode is in ph 7.01 beaker and wait for the “Err4” to disappear.
• After approximately 30 seconds, press the CON key to confirm the calibration.


The printer will print further instructions for the calibration procedure.



The LCD will show “Err5” to indicate that the electrode is now ready for slope calibration.
• Immerse the probe into 4.01 or 10.01 solution.










The LCD will show the corresponding buffer vaue at the working temperature.








• Wait approximately 30 seconds,and then press the CON key to confirm the calibration.