Metrohm 761 Compact IC - Manual (Page 48)

2 Installation
761 Compact IC
38
2.8 Suppressor module
2.8.1 General information on suppressor module
The Metrohm Suppressor Module MSM for chemical suppression
installed in the 2.761.0020 Compact IC comprises a total of 3 suppres-
sor units which are in turn used for suppression, regenerated with sulfu-
ric acid and rinsed with water. To record every new chromatogram un-
der comparable conditions, work is normally carried out with freshly
regenerated suppressor. Switching is either automatic together with the
valve switching or manual.
The suppressor units must never be regenerated with H
2
SO
4
in the
same flow direction used for the eluent. You should thus always install
the inlet and outlet capillaries as described in section 2.8.4 according
to the scheme shown in Fig. 18.
For operation of the suppressor module, the two-channel peristaltic
pump built into the 2.761.0020 Compact IC is used which conveys the
regeneration solution (normally 20 mmol/L H
2
SO
4
) and the rinsing so-
lution (normally dist. H
2
O) to the suppressor units (flow rate of 0.5
mL/min).
The three inlets and outlets numbered 1...3 on the suppressor module
each have 2 permanently mounted PTFE capillaries, which must be
connected as described in section 2.8.4 (see Fig. 16 and Fig. 18).
To avoid contamination of the suppressor module by foreign particles
or bacterial growth, the two 6.2821.120 Filter units PEEK (see sec-
tion 2.3.6) supplied with the 2.761.0020 Compact IC must be installed
between the peristaltic pump and the inlet capillaries of the suppressor
module.
The suppressor module must never be switched in the dry state as
there is a danger of blocking. Before every switching operation of the
suppressor module, the three suppressor units must have been
rinsed for at least ½ h with eluent, regeneration and rinsing solution.
2.8.2 Preparation of the peristaltic pump
Before start-up the accessories for the 2-channel peristaltic pump built
into the 761 Compact IC must be mounted according to Fig. 15. Pro-
ceed as follows:
1 Attach pump tubings
• Loosen both tubing cartridges 48 mounted above pump drive
52 from the holding clamp 50 by pressing down snap-action
lever 51 and remove from mounting pin 53 (see Fig. 16).