wtw PB 150, Руководство по эксплуатации

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Overview
16
1.4.2 Sampling according to flow
Note
For the sampling according to flow, a flow quantity counter is required
additionally.
The sampling according to flow can be performed using an analog or a
digital flow signal.
Analog
flow signal
The number of samplings per time unit depends on the flow signal. The
number of samplings in case of the maximum analog flow signal (0-20
mA) is fixed.
The dosing volume of the individual samples remains the same.
In case of maximum flow, an analog flow counter sends the maximum
flow signal (e. g. 20 mA).
Digital
flow signal
The number of samplings per time unit depends on the flow signal. The
number of samplings in case of the maximum analog flow signal (puls-
es/time unit) is fixed.
The dosing volume of the individual samples remains the same.
In case of maximum flow, a digital flow counter sends e. g. 1000 pulses
per hour (setting at the flow counter).
analog
signal the frequency of the sampling corresponds to the
strength of current that occurs
digital
signal
the frequency of the sampling corresponds to the
number of flow pulses per time unit
Example: Setting in the menu:
Flow signal: analog 0-20 or 4-20 mA
Maximum number of samples per hour: 40
Result:
With a flow signal of 20 mA, 40 samples per hour are
taken.
With a flow signal of 20 mA, 10 samples per hour are
taken.
Example: Setting in the menu:
Flow signal: digital
Pulse divider: 25
Result:
With 1000 pulses per hour, 40 (= 1000:25) samples are
taken.
With 500 pulses per hour, 20 (= 500:25) samples are
taken.