Measurement support
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:
• 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
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 Section 9.2.1 for instructions on this method.
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.
c.
Calculate the meter factor using the following formula:
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Micro Motion 9739 MVD Transmitters