Metrohm viva 1.1 - Manual (Page 1053)

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9 Support
viva 1.1
￭￭￭￭￭￭￭￭ 1041
Problem Cause Remedy
One or several electrodes
are defective. Perform maintenance in accordance with the
electrode leaflet.
The measuring vessel con-
tains too little solution or is
empty. Check the fill level in the measuring vessel and
add solution if necessary.
The electrode tip of
the working elec-
trode and/or the
auxiliary electrode
shows copper
deposits. An incorrect potential has
been applied because the
reference electrode is
defective. ￭ Check the reference electrode; perform
maintenance procedure in accordance with
the electrode leaflet, if necessary.
￭ 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 refer-
ence electrode is not con-
nected. ￭ Check the electrode connectors.
￭ 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).