Metrohm 884 Professional VA, Руководство - Краткие инструкции

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6.1 List of faults
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884 Professional VA
Problem Cause Remedy
￭
The retaining screw is too loose or too
tight. Use the wrench for MME
(6.1247.220) to tighten the retaining screw
to the right torque.
The electrolyte solution is
too old. Produce new electrolyte solution. Organic
additives may only last 1 day or less.
The mercury in the MME
pro displays the black
streaks of mercury oxide. Completely remove and clean the electrode
(see the
Multi-Mode Electrode pro document
(8.110.8018XX) ).
The reference electrode is
not filled correctly (inside
and outside). Top up the reference electrode.
The reference electrode's
diaphragm is partially or
completely blocked (e.g.
from precipitation caused
by incompatible solutions
like KCl as a bridge electro-
lyte and HClO
4
as an elec-
trolyte in the measuring
solution).
Ensure the compatibility of the chemistry.
Replace the bridge electrolyte if necessary
(such as using a NaCl or KNO
3
solution in place
of KCl).
Curves have a large
amount of noise
(with DME/SMDE). The electrode drips at irreg-
ular intervals.
￭
Check the tapping of the dripping on the
MME pro. If necessary, center the capillary
in the MME pro or readjust the anchoring
of the capillary using the wrench for the
MME (6.1247.220).
￭
Adjust the needle and capillary.
￭
If necessary, replace the capillary or needle
(see the
Multi-Mode Electrode pro docu-
ment (8.110.8018XX) ).
The electrode drips too
quickly (with DME). Increase the voltage step time in the voltam-
metry command on the
Sweep tab.
Curves have a large
amount of noise
(with HMDE). The electrode surface is
overloaded. Check the deposition potential and time and
reduce them if necessary.
No drops form at the capil-
lary.
￭
Check the nitrogen connection and pres-
sure.
￭
Ensure that the measuring head is attached
correctly and locked in place.