Metrohm viva 1.0 (process analysis) - Manual (Page 964)

9.2 Troubleshooting
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952 ￭￭￭￭￭￭￭￭
viva 1.0 (for Process analysis)
Problem Cause Remedy
￭ Dip the electrode tip of the working elec-
trode and/or the auxiliary electrode into
concentrated nitric acid for 1 to 2 seconds
and then thoroughly rinse with distilled
water.
An incorrect potential was
applied because the mea-
suring vessel contains too
little measuring solution. ￭ All three electrodes must be immersed in
the measuring solution.
￭ Dip the electrode tip of the working elec-
trode and/or the auxiliary electrode into
concentrated nitric acid for 1 to 2 seconds
and then thoroughly rinse with distilled
water.
The measured val-
ues are widely scat-
tered. The solutions are pipetted
manually. Use an 800 Dosino with dosing unit.
The solutions are not
added via the pipetting
opening. Add solutions only via the pipetting opening
(see Manual 894 Professional CVS).
The measurement
curves are noisy. Contact problem at the
driving axle (6.1204.510 or
6.1204.520). ￭ Remove the abrasion residue from the driv-
ing axle.
￭ Replace the driving axle.
The measuring sig-
nal for Cu VMS fluc-
tuates. The ambient and/or solu-
tion temperature is not
constant. Keep the ambient and solution temperature
stable during measurements (±4 °C).
The reference potential
drifts off. Perform maintenance procedure for the refer-
ence electrode in accordance with the elec-
trode leaflet. However, for CVS analyses,
replace the reference electrolyte every other
day and the bridge electrolyte every day.
The measuring vessel and
the electrodes have been
contaminated with organic
additives. Thoroughly rinse the measuring vessel and the
electrodes and use fresh VMS.
The measuring ves-
sel overflows. Incorrect pump times have
been defined in viva. Adjust the pump times.
The volumes defined in the
dosing commands in viva
are too large. Reduce the volumes.