Endress+Hauser ASP Station 2000 Mode D'emploi page 120

10 Technical data
120
Fig. 54: Dosing system
Item A: conductivity probe (long)
Item B: conductivity probe (long)
Item C: conductivity probe (short)
Item D: dosing pipe
There are three conductivity probes in the dosing funnel lid. During the suction process, the sample
liquid first reaches the longer conductivity probes (item A and B). In this way, the filling of the
dosing funnel is detected and the suction process is stopped. If the conductivity probes (item A and
B) fail, safety switch-off takes place by means of the shorter conductivity probe (item C).
• The sample volume is set between 20 ml and 200 ml by moving the dosing pipe (item D).
• The dosing system can be disassembled and cleaned easily without tools.
• A special dosing system is required for flow-proportional sampling (see ordering information).
There are four stages in the sampling process:
Fig. 55: Sampling
1 Blow out: The diaphragm pump blows the suction line clear via the dosing system.
2 Suction: the "Air manager" prepares the air passage of the diaphragm pump for suction. The sample liquid is drawn
into the dosing funnel until the conductivity probes of the dosing system respond.
3 Dosing: the diaphragm pump ends the suction process. Depending on the position of the dosing pipe (item D), the
excess sample liquid flows back to the sampling point.
4 Drain: the hose constriction is opened and the sample is drained into the sample bottle.
ASP Station 2000
Endress+Hauser