Parkside PPHM 14 A1 Bedienungs- Und Sicherheitshinweise Seite 28

Verification check result
Successful: The display 6 shows the approximate
pH value of the respective pH buffer solution on all
3 verification checks: The product has passed the
verification check. The product is ready to measure the
pH value of liquids (see "Taking a measurement").
28 GB
Fail: The pH values shown in the display 6 are
totally wrong or do not match closely with the
respective pH buffer solution for any of the 3 pH buffer
solutions:
The verification check has failed for that particular
pH buffer solution. Perform manual calibration
for the failed pH buffer solution(s) (see "Manual
calibration").