Measurement support
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.
3.
Configure the meter factor in the transmitter.
• To set the meter factor using the display:
OFF-LINE MAINT→CONFG→UNITS→MTR F
• To set the meter factor using ProLink II:
ProLink→Configuration→Flow
• To set the meter factor using the Field Communicator:
−
Configure→Manual Setup→Measurements→Flow
−
Configure→Manual Setup→Measurements→Density
t
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. A mass flow
meter factor is determined as follows:
The first meter factor for mass flow is 0.9989.
One year later, the flowmeter is validated again. The flowmeter mass measurement is 250.07 lb; the
reference device measurement is 250.25 lb. A new mass flow meter factor is determined as follows:
The new meter factor for mass flow is 0.9996.
9.2.1
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 Section 9.2).
2.
Calculate the meter factor for volume flow from the meter factor for density:
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