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Ultrasonic flow meter
SU2020 SU8020 SU2021 SU8021 SU2621 SU8621
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10.4.5 Output polarity of the switching outputs
The parameter [P-n] can be used to select whether the outputs are plus-switching or negative-
switching.
10.4.5.1 Parameter setting via unit keys: Output polarity
u
Call up the menu [EF] > [CFG].
u
Select [P-n] and set [PnP] or [nPn].
10.4.5.2 Parameter setting via IO-Link: output polarity
u
Select [Parameters] > [Setup].
u
Select [P-n] and set [PnP] or [nPn].
10.4.6 Low flow cut-off
With the function low flow cut-off [LFC] it is possible to suppress small volumetric flow quantities.
Volumetric flow below the LFC value is evaluated by the sensor as standstill (Q = 0).
10.4.6.1 Parameter setting via unit keys: low flow cut-off
u
Call up the menu [EF] > [CFG].
u
Select [LFC] and set the limit below which a flow is evaluated as standstill.
10.4.6.2 Parameter setting via IO-Link: low flow cut-off
u
Select [Parameter] > [More settings] > [Flow].
u
Select [LFC] and set the limit below which a flow is evaluated as standstill.
10.4.7 Flow direction
The positive flow direction can be defined by the user. This setting affects the following functions:
•
Counting method of the totalisers
•
flow direction monitoring via switching signal
Switching signal for flow direction
An arrow with the text “flow direction” on the unit indicates the positive flow direction (factory setting).
The direction of the flow measurement can be reversed using the parameter [Fdir].
+
Flow direction in case of factory setting
-
Flow direction contrary to the factory setting
10.4.7.1 Parameter setting via unit keys: flow direction
u
Call up the menu [EF] > [CFG].
u
Select [Fdir] and set the direction of media flow.
10.4.7.2 Parameter setting via IO-Link: flow direction
u
Select [Parameter] > [More settings] > [Flow].
u
Select [Fdir] and set the direction of media flow.