Walchem W100 - Electrode Reading Responds Slowly; Electrode Cleaning and Calibration Procedures; Electrode Replacement for Unresponsive Readings

CAUTION: There are live circuits inside the controller even when the power switch is in the
OFF position! Servicing and troubleshooting the controller must be performed by
Qualified
Service Personnel.
3
Section 1: Electrode Reading Responds Slowly
Step 1:
pH electrodes require periodic cleaning and calibration.
 The method of cleaning the electrode will depend upon the coating, as well as the
materials of construction of the electrode. Do not use a solvent that will attack the
electrode.
 Oily coatings should be removed with a mild detergent or isopropyl alcohol.
 Hard scales such as calcium carbonate can usually be removed with a dilute
hydrochloric acid solution.
 Soft coatings can be removed using a soft cloth or soft toothbrush.
 A two-point calibration should always be performed after cleaning the electrode.
Step 2:
If cleaning does not speed up the electrode's response
 Replace the electrode.