Emerson MMI-20019043 Manuel D’Utilisation
Procedure
1.
Determine the meter factor as follows:
a. Use the flowmeter to take a sample measurement.
b. Measure the same sample using the reference device.
c. Calculate the meter factor using the following formula:
b. Measure the same sample using the reference device.
c. Calculate the meter factor using the following formula:
NewMeterFactor
ConfiguredMeterFactor
ReferenceMeasurement
FlowmeterMeasurement
=
x
2.
Ensure that the calculated meter factor is between 0.8 and 1.2, inclusive. If the
meter factor is outside these limits, contact Micro Motion customer service.
meter factor is outside these limits, contact Micro Motion customer service.
3.
Configure the meter factor in the transmitter.
Example: Calculating the meter factor for mass flow
The flowmeter is installed and validated for the first time. The mass flow measurement
from the transmitter is 250.27 lb. The mass flow measurement from the reference device
is 250 lb. The mass flow meter factor is calculated as follows:
from the transmitter is 250.27 lb. The mass flow measurement from the reference device
is 250 lb. The mass flow meter factor is calculated as follows:
MeterFactor
MassFlow
1
250
250.27
=
x
= 0.9989
The first meter factor for mass flow is 0.9989.
One year later, the flowmeter is validated again. The mass flow measurement from the
transmitter is 250.07 lb. The mass flow measurement from the reference device is
250.25 lb. The new mass flow meter factor is calculated as follows:
transmitter is 250.07 lb. The mass flow measurement from the reference device is
250.25 lb. The new mass flow meter factor is calculated as follows:
MeterFactor
MassFlow
0.9989
250.25
250.07
250.07
=
x
= 0.9996
The new meter factor for mass flow is 0.9996.
11.4.1
Alternate method for calculating the meter factor for
volume flow
The alternate method for calculating the meter factor for volume flow is used to avoid the
difficulties that may be associated with the standard method.
difficulties that may be associated with the standard method.
This alternate method is based on the fact that volume is inversely proportional to density.
It provides partial correction of the volume flow measurement by adjusting for the portion
of the total offset that is caused by the density measurement offset. Use this method only
when a volume flow reference is not available, but a density reference is available.
It provides partial correction of the volume flow measurement by adjusting for the portion
of the total offset that is caused by the density measurement offset. Use this method only
when a volume flow reference is not available, but a density reference is available.
Procedure
1.
).
2.
Calculate the meter factor for volume flow from the meter factor for density:
Measurement support
Configuration and Use Manual
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