10 Technical data
ASP station 2000
104
EHauser
Fig. 48:
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. 49:
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.
