wtw PB 150, Operating Manual

Page: 14 / 108

Overview
14
1.3 Course of sampling
Sampling is performed in the following steps.
1 Blowing free the dosage unit and suction hose:
The squeezing valve closes the sample outlet.
The membrane pump creates pressure and pumps air into the
dosing glass. By this, the sample left in the connected suction
hose is displaced and the suction hose is cleaned.
2 Taking in sample:
The valve system switches to vacuum. The vacuum in the
dosage vessel created by the membrane pump leads to a
suction effect at the suction hose connected.
The dosing glass is filled with sample.
As soon as the sample reaches the electrodes (conductive fill-
ing level measurement via the conductivity of the medium), the
membrane pump is switched off.
3 Adjusting the sample volume:
The valve system switches to pressure. The membrane pump
creates a pressure in the dosage vessel. This pressure
displaces the superfluous sample from the dosing glass. The
sample quantity is adjusted to the height of the dosage tube.
The sample left in the connected suction hose is displaced and
the suction hose is cleaned.
4 Bottling the sample:
After the specified ventilation time the squeezing valve opens
and the sample flows off into a sample bottle.
zu zu zu auf
Druck Druck Vakuum
Leitung
freiblasen
Freies
Ablaufen
Probe ansaugen
bis Kontakt
Leitung freiblasen,
Probe abdosieren
Probe
abfüllen