Metrohm 820 IC Separation Center - Manual (Page 78)

4 Notes - Maintenance - Faults
819 IC Detector / 820 IC Separation Center
70
Maintenance by Metrohm service
Maintenance of the 819 IC Detector and 820 IC Separation Center is
best done as part of an annual service performed by specialists from
the Metrohm company. If work is frequently performed with caustic and
corrosive chemicals, it may be necessary to shorten the interval be-
tween servicing.
The Metrohm service department is always willing to offer expert advice
on the maintenance and servicing of all Metrohm instruments.
4.2.2 Passivation
Passivation of the entire IC system (without column) by rinsing with
20...50 mL 0.2 mol/L HNO
3
is appropriate only in the following case:
• if exceptional changes are observed in the
measurement properties of the cell
For passivation the separating column is removed from the 820 IC
Separation Center. The two capillaries 50 and 57 (see Fig. 21 and Fig.
23) are connected directly to each other with the 6.2744.040 Coupling
71 included in the accessories.
4.2.3 Recycling
To keep the eluent consumption between injections to a minimum when
the system is at rest (e.g. overnight), the so-called recycling procedure
can be used. In recycling the eluent exiting the outlet capillary of the
detector block is led back directly to the eluent supply vessel. The IC
system is thus quickly ready for new injections without a long condition-
ing period.
The recycling procedure must not be used
• in operation with the suppressor module,
• with alkaline eluents,
with the 6.1010.000 IC Cation column METROSEP Cation 1-2.
4.2.4 Shutdown
If the 819/820 IC-System is shut down for a considerable length of time,
the entire IC system (without column and suppressor) must be rinsed
free from salt with methanol/water (1:4) to avoid crystallization of elu-
ent salts with the corresponding subsequent damage.
For rinsing the separating column is removed; the two capillaries 50
and 57 (see Fig. 21 and. Fig. 23) are directly connected to each other
with the 6.2744.040 Coupling enclosed with the accessories. Rinse with
methanol/water (1:4) until the conductivity drops below 10 µ S/cm.