Emerson Micro Motion 5700 Configuration And Use Manual page 34

Configure process measurement
March 2019
Mass Flow Cutoff specifies the lowest mass flow rate that will be reported as measured. All mass flow rates
below this cutoff will be reported as 0.
Procedure
Set Mass Flow Cutoff to the value you want to use.
• Default: A sensor-specific value set at the factory. If your transmitter was ordered without a sensor, the
default may be 0.0.
• Recommendation: 0.5% of maximum flow rate of the attached sensor. See the sensor specifications.
Important
Do not use your meter for measurement with Mass Flow Cutoff set to 0.0 g/sec. Ensure that Mass Flow
Cutoff is set to the value that is appropriate for your sensor.
Effect of Mass Flow Cutoff on volume measurement
Mass Flow Cutoff does not affect volume measurement. Volume data is calculated from the actual mass data
rather than the reported value.
Volume flow has a separate Volume Flow Cutoff that is not affected by the Mass Flow Cutoff value.
Interaction between Mass Flow Cutoff and mA Output Cutoff
Mass Flow Cutoff defines the lowest mass flow value that the transmitter will report as measured. mA
Output Cutoff defines the lowest flow rate that will be reported via the mA Output. If mA Output Process
Variable is set to Mass Flow Rate, the mass flow rate reported via the mA Output is controlled by the higher of
the two cutoff values.
Mass Flow Cutoff affects all reported values and values used in other transmitter behavior (e.g., events
defined on mass flow).
mA Output Cutoff affects only mass flow values reported via the mA Output.
Cutoff interaction with mA Output Cutoff lower than Mass Flow Cutoff
Configuration:
• mA Output Process Variable: Mass Flow Rate
• Frequency Output Process Variable: Mass Flow Rate
mA Output Cutoff: 10 g/sec
•
Mass Flow Cutoff: 15 g/sec
•
Result: If the mass flow rate drops below 15 g/sec, mass flow will be reported as 0, and 0 will be used in all
internal processing.
Cutoff interaction with mA Output Cutoff higher than Mass Flow Cutoff
Configuration:
• mA Output Process Variable: Mass Flow Rate
Frequency Output Process Variable: Mass Flow Rate
•
• mA Output Cutoff: 15 g/sec
34
Configuration and Use Manual
Micro Motion Model 5700 with Ethernet Transmitters
MMI-20029769