Alternate Method For Calculating The Meter Factor For Volume Flow - Emerson Micro Motion 5700 Configuration And Use Manual

Configuration and Use Manual
MMI-20025166
Obtain a reference device (external measurement device) for the appropriate process variable.
Important
For good results, the reference device must be highly accurate.
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.
NewMeterFactor = ConfiguredMeterFactor ×
c) Calculate the meter factor using the following formula:
2. Ensure that the calculated meter factor does not fall outside 0.98 and 1.02. If the meter factor is
outside these limits, contact customer service.
3. Configure the meter factor in the transmitter.
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:
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:
The new meter factor for mass flow is 0.9996.
14.5.1 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.
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.
Procedure
1. Calculate the meter factor for density, using the standard method (see
2. Calculate the meter factor for volume flow from the meter factor for density:
Configuration and Use Manual
MeterFlow = 1 x
MassFlow
MeterFlow = 0.9989 x
MassFlow
ReferenceMeasurement
FlowmeterMeasurement
250
= 0.9989
250.27
250.25
= 0.9996
250.07
Validate the
Measurement support
March 2019
meter).
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