Voith BTG Mutek PCD-06, Руководство по эксплуатации

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48 Operation Manual Mütek
TM
PCD-06 © BTG 2021
VI. Diagnostics and troubleshooting
6.3.2 Basic faults
The following basic faults may be experienced with the Mütek™ PCD-06 also when used in combination with an exter-
nal titrator:
Problem Cause Solution
Heavy fluctuations of strea-
ming potential after sample
is filled in
- Excessive conductivity of the
sample
• Dilute sample.
- Insufficient sample volume in mea-
suring cell
• Weigh in once again or use
pipette.
- High solids in the sample • Dilute the sample or centrifuge/
screen it to remove coarse par-
ticles.
Potential reverses after
reaching the endpoint
- Very slow reaction between titrant
and sample
• Titrate more slowly or perform
back titration.
• If necessary, check sample prepa-
ration for homogeneity.
At the start of titration,
potential increases instead
of decreasing
- Wrong titrant • Select titrant with opposite charge
to that of sample.
- Adsorption equilibrium not attained • Proceed slowly with titration.
- Sample concentration too high or
titrant concentration too low
• Dilute sample.
Potential remains essenti-
ally unchanged during titra-
tion
- Sample concentration very high • Dilute sample or use a higher
strength titrant.
- Wet contacts on Mütek™ PCD-06 • Dry contact pins with a soft cloth.
- Wet electrodes on the outside of
the measuring cell
• Dry electrodes with a soft cloth.
- Measuring cell contaminated • Thoroughly clean measuring cell
and displacement piston.
Sign of displayed potential
not in conformity with
sample specification
- Sample charge is pH dependent • Check on pH dependence of
sample.
- Excessive viscosity • Dilute sample.
- Measuring cell contaminated • Thoroughly clean measuring cell
and displacement piston.