Some issues with a pH measurement are:
Check this list of possible reasons: Guide to troubleshooting
Many measurement problems arise from the electrode or from a wrong use, rarely from the instrument itself. Therefore it is important to:
We need some information to be able to help. There are several manners to return the information that is requested in the grey box here below: you can print this page or export it as pdf and fill in the information at the desired location. It is also possible to: Select and Copy the text in the grey box here below, paste it into a new email message and fill in the requested items before sending it to Consort support (click this to open your email editor).