Emerson Micro Motion 5700 Configuration And Use Manual page 185

Prerequisites
Identify the meter factor(s) that you will calculate and set. You may set any combination of
the three meter factors: mass flow, volume flow, and density. Note that all three meter
factors are independent:
•
•
•
Important
To adjust volume flow, you must set the meter factor for volume flow. Setting a meter factor for
mass flow and a meter factor for density will not produce the desired result. The volume flow
calculations are based on original mass flow and density values, before the corresponding meter
factors have been applied.
If you plan to calculate the meter factor for volume flow, be aware that validating volume
in the field may be expensive, and the procedure may be hazardous for some process
fluids. Therefore, because volume is inversely proportional to density, an alternative to
direct measurement is to calculate the meter factor for volume flow from the meter factor
for density. See
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.
2.
3.
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:
Configuration and Use Manual
The meter factor for mass flow affects only the value reported for mass flow.
The meter factor for density affects only the value reported for density.
The meter factor for volume flow affects only the value reported for volume flow or
gas standard volume flow.
Section 12.4.1 for instructions on this method.
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:
NewMeterFactor = ConfiguredMeterFactor
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.
Configure the meter factor in the transmitter.
Measurement support
ReferenceMeasurement
FlowmeterMeasurement
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