Peristaltic Pump And Injection Valve; Figure 15 Measuring The Volume - Filling The Sample Loop - Metrohm 942 Extension Module Vario LQH Manual

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7.3

Peristaltic pump and injection valve

Figure 15 Measuring the volume – Filling the sample loop
1 Sample
3 Injection valve
942 Extension Module Vario LQH (2.942.0070)
The peristaltic pump and the injection valve are used for precisely measur-
ing small volumes.
The liquid to be dosed, such as the sample (15-1), is pumped using the
peristaltic pump (15-2) into the sample loop (15-4) at the injection valve
(15-3). The desired volume is defined precisely by the size of the selected
sample loop.
1
2
After the valve switchover (16-2), the measured sample segment is pum-
ped (16-5) by aspiration using the Dosino (16-1) through the 10-port
valve (16-4) into the transfer tubing (16-6) and can be pumped further to
another port from there.
3
1
10
2
9
3
8
4
7
5
6
4
2 Peristaltic pump
4 Sample loop
7 Mode of operation
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