Endress+Hauser Liquistation CSF39, Руководство по эксплуатации

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Liquistation CSF39 Operation
Hauser 75
Type of sampling Example Info
Time/flow-paced (only
possible with peristaltic
pump) Time/flow-paced Controlled via current input
• Signal: 0 to 20 mA
•
Sampling interval : 10 min
• Sampling volume : variable
The maximum sampling volume is defined at
the maximum flow rate. Example: The
maximum flow rate at 20 mA at the current
input is 160 l/s, and the maximum sampling
volume is 200 ml. When transferring
samples into a 30l mixed sample container,
144 samples are taken per day with a
maximum sampling volume of 28.8 l. With a
flow rate of 80 l/s, a sampling volume of
only 100 ml would be grabbed, and a
sampling volume of 50 ml would be grabbed
at a flow rate of 40 l/s. The sampling volume
is always calculated based on the flow.
Controlled via binary input
• Binary input (pulse per flow unit)
•
Sampling interval : 10 min
• Sampling volume : variable
The sampling volume is defined for a flow
pulse, e.g.: 1 pulse is 20 ml. For instance, if 5
flow pulses are counted between the
sampling intervals, this results in a sampling
volume of 5 x 20 = 100 ml, and a volume of
8 x 20 = 160 ml for 8 pulses. If a binary
input is used for time/flow-paced sampling,
the sampling volume is calculated per sample
as a percentage of the specified sampling
volume.
Samples are taken at set intervals
with a variable sampling volume.
The sampling volume is calculated
from the flow rate. More volume
is grabbed when the flow is high
than when it is low. Since the flow
normally fluctuates and the
maximum flow is only rarely a
constant variable, the sampling
volume transferred to the
container will depend on the daily
average.
Advantage:
Very good, representative
sampling given large fluctuations
in the flow and constant time
intervals.
Disadvantage:
Too little sampling volume is
made available for analysis when
the flow is low.
Advantage with current input:
For the sampling interval, either
the current flow rate or the
average value between the last
and current flow rate is used to
calculate the exact sampling
volume (depending on the
presetting).
Disadvantage with binary input:
For the sampling interval, the
pulses counted since the last
sampling are multiplied by a
volume. If this is too high - e.g.
100 ml - the composition of the
sample is not representative for
analysis.
Event Event-based sampling is controlled via the
current input, binary input and/or sensor
input. The subprogram created waits to be
activated by an event that can consist of up
to 3 individual events. Every possible
condition can be created using logical "and" /
"or" links. For example, the information from
a flowmeter connected to the current input
can be linked to a rain gage and a pH sensor
signal connected to the binary input. An
event is defined as limit value violation
(exceeded or undershot), range monitoring
within or outside a range, or a rate of
change. Users can decide whether additional
sampling is started when the event starts
and/or ends. For the duration of the event,
users can choose from time-paced, flow-
paced or time/flow-paced sampling, or can
take single samples, use a sampling table or
the external control system. The sampler waits for an event.
This event takes place via internal
sensor signal processing or via
devices connected externally. As
bottle assignment is possible
when using several bottles, events
can be assigned to individual
bottles. A maximum of 24
subprograms can be started
simultaneously and assigned to
individual bottles.
Bottle synchronization
The bottle synchronization setting is possible with all types of program. In addition, bottle
synchronization can be switched via an external signal. Bottle synchronization is only
possible with a bottle change after a specific time and not with a bottle change after a
number of samples.