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ANNEX - VAR variable sampling system-
The VAR variable sampling system enables a flow-proportional sample extraction, that
means the sample volume varies automatically according to an analog flow signal
(0/4 - 20mA).
Example:
- the selected range is 0 to 20 mA
- the max. sample volume at
20 mA
is fixed to
200 ml.
That means at an analog signal of e.g.
10 mA,
a
100 ml
sample would be extracted. Thus
the sample extraction is always proportional to the flow.
At this system the sampling interval is
fixed
(e.g. every 10 min.) and the sample volume
varies
(the volume changes according to the mA signal).
Thus a sample extraction
proportional
to the flow
is guaranteed.
When putting the sampler into service, the system has to be
calibrated.
How to do the
calibration is described in the following:
Settings
device settings
calibration VAR system
• CALIBRATION
1.
Setting of suction height (range)
2.
Start
lower
value
There are 3 consecutive calibration cycles which are started
automatically.
Please collect the samples of all 3 cycles in a measuring glass!
