Metrohm 790 Personal IC - Manual (Page 165)

5 Notes – Maintenance – Faults
790 Personal IC
156
5.2.3 Recycling
To keep the eluent consumption between injections to a minimum
when the system is at rest (e.g. overnight), the so-called recycling pro-
cedure 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 condi-
tioning 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.
5.2.4 Shutdown
If the 790 Personal IC 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 connections to the separating column and the suppres-
sor module are removed; the two capillaries 20 20 20 20 and 37 37 37 37 (see Fig. 13 and
Fig. 15) are directly connected to each other using coupling 26 26 26 26
(6.2620.060). Rinse with methanol/water (1:4) until the conductivity
drops below 10 µS/cm.
5.2.5 Changing separating columns
Identical separation system
If you wish to replace an IC separating column by a column of the same
type, proceed as follows (see Fig. 13 and Fig. 15):
1 Remove old column
• Switch off high-pressure pump and wait for pressure to drop.
• Unscrew column 63
63 63 63 from inlet capillary 37 37 37 37 of the detector
block or from suppressor inlet capillary 78 78 78 78.
• Unscrew column 63 63 63 63 from column connection capillary 20 20 20 20 or
the precolumn.
2 Connect new column to injector
• Remove end caps from column 63 63 63 63.
• Screw inlet end of separating column 63 63 63 63 (note flow direction)
to column connection capillary 20 20 20 20 or to the precolumn (see
section 2.7.7/section 2.7.8).