Emerson MMI-20019043 Manuel D’Utilisation

Set Mass Flow Cutoff to the value you want to use.

The default value for Mass Flow Cutoff is 0.0 g/sec or a sensor-specific value set at the
factory. The recommended setting is 0.05% of the sensor's rated maximum flow rate or a
value below the highest expected flow rate. Do not set Mass Flow Cutoff to 0.0 g/sec.

Mass Flow Cutoff

 does not affect volume measurement. Volume data is calculated from the

actual mass data rather than the reported value.

Mass Flow Cutoff

 defines the lowest mass flow value that the transmitter will report as

measured. AO 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).

AO Cutoff

 affects only mass flow values reported via the mA output.

Configuration:

•

mA Output Process Variable

: Mass Flow Rate

•

Frequency Output Process Variable

: Mass Flow Rate

•

AO 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.

Configuration:

•

mA Output Process Variable

: Mass Flow Rate

•

Frequency Output Process Variable

: Mass Flow Rate

•

AO Cutoff

: 15 g/sec

•

Mass Flow Cutoff

: 10 g/sec

Result:

•

If the mass flow rate drops below 15 g/sec but not below 10 g/sec:

-

The mA output will report zero flow.

Configure process measurement

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