Siemens SITRANS F M Intermag 2, Руководство по эксплуатации

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Operation
5-29
SITRANS FM Intermag 2 Flow Transmitter
Operating Manual - A5E00102775-03
S
Low flow cut , menu item 3.1.6
This parameter determines the switching point for low flow cut. The
low flow cut prevents flow being measured in the lower range (e.g.
fluctuating liquid columns at a standstill). The low flow cut affects:
display, totalizers, analog output and pulse frequency output as well
as HART and PROFIBUS communication.
In devices with HART communication, the value of the low flow is
related percentage-wise to the upper range value (menu item
3.1.2.
In devices with PROFIBUS communication, the absolute value must
be entered in the selected unit of flow (menu item
3.1.1 ).
S
Filter time constant , menu item 3.1.7.1
The jump response can be suppressed in this menu item. This may
be necessary depending on the application, for example in the case
of fast changing flows to keep the display value or analog value
calm.
S
Line synchronization , menu item 3.1.7.2
In the case of a DC power supply to the transmitter, this parameter
may not be set to “on”.
S
Noise Suppress , menu item 3.1.7.3
This function serves to eliminate temporary, application-related
interference within a fixed time window.
Every measured value within a measuring pulse is compared with
the previously determined value. If it is outside the tolerance band
set under menu item
3.1.7.3 (the specified % value refers to the set
full scale value), the device operates with a filter time constant
of 10 s.
This applies for the suppress time set in menu item
3.1.7.3 . If a
greater deviation occurs during this time, the time starts again from
the beginning. If a disturbed signal is applied continuously, the
device remains set to the greater filter time constant until the
unattenuated measured values are back within the selected
tolerance band. The device switches back over to normal mode at
the end of time ”t” after the last detected deviation.