Emerson Micro Motion 2500 Configuration And Use Manual page 34

Configure process measurement
Overview
Volume Flow Cutoff specifies the lowest volume flow rate that will be reported as
measured. All volume flow rates below this cutoff are reported as 0.
Procedure
Set Volume Flow Cutoff to the value you want to use.
The default value for Volume Flow Cutoff is 0.0 l/sec (liters per second). The lower limit is
0.
Interaction between Volume Flow Cutoff and mAO Cutoff
Volume Flow Cutoff defines the lowest liquid volume flow value that the transmitter will
report as measured. mAO Cutoff defines the lowest flow rate that will be reported via the
mA Output. If mA Output Process Variable is set to Volume Flow Rate, the volume flow rate
reported via the mA Output is controlled by the higher of the two cutoff values.
Volume Flow Cutoff affects both the volume flow values reported via the outputs and the
volume flow values used in other transmitter behavior (e.g., events defined on the volume
flow).
mAO Cutoff affects only flow values reported via the mA Output.
Example: Cutoff interaction with mAO Cutoff lower than Volume Flow Cutoff
Configuration:
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Result: If the volume flow rate drops below 15 l/sec, volume flow will be reported as 0, and
0 will be used in all internal processing.
Example: Cutoff interaction with mAO Cutoff higher than Volume Flow Cutoff
Configuration:
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Result:
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mA Output Process Variable: Volume Flow Rate
Frequency Output Process Variable: Volume Flow Rate
AO Cutoff: 10 l/sec
Volume Flow Cutoff: 15 l/sec
mA Output Process Variable: Volume Flow Rate
Frequency Output Process Variable: Volume Flow Rate
AO Cutoff: 15 l/sec
Volume Flow Cutoff: 10 l/sec
If the volume flow rate drops below 15 l/sec but not below 10 l/sec:
- The mA Output will report zero flow.
- The Frequency Output will report the actual flow rate, and the actual flow rate
will be used in all internal processing.
Micro Motion Model 2500 Transmitters with Configurable Input/Outputs