Mass Compensation Panel - Emerson Micro Motion 3711 Configuration And Use Manual

Configuring Volumetric Flow Measurement
Table 6-1 Input Defs parameters continued
Parameter Description
Density Input Definitions
Base Density Specify the point from which the base density value will be
Source read.
Flowing Density Specify the point from which the flowing density value
Source value will be read.
Gas Properties Displays the calculation method that will be applied to the
Calculation sensor data.
Method
Averaging Technique Specify how averages will be calculated:
• Flow Dependent Linear: Discards samples for periods
when there is no measurable flow, and performs a linear
average of the remaining samples to compute the minute
and hour values for archiving.
• Flow Dependent Formulaic: Discards samples for
periods when there is no flow, and calculates the
average by averaging the square root of each sample,
then squaring the result.
• Flow Weighted Linear: No samples are discarded. Each
sample is weighted by multiplying it by the mass flow
rate. The linear average is calculated by dividing the sum
of the flow-weighted sample by the sum of the flow
values.
• Flow Weighted Formulaic: Combines the weighting
technique and the formulaic averaging technique.
6.3.2

Mass Compensation panel

The Mass Compensation panel is shown in Figure 6-2. This panel is used to enable or disable pressure
compensation for mass flow measurement, and define the pressure correction factors for your
particular sensor. It also displays the results of the pressure compensation calculation. Parameters on
this panel are listed and defined in Table 6-2.
Note: Not all sensors or applications require pressure correction factors. For a discussion of pressure
effect, see the EXPERT
correction, see the product data sheet for your sensor.
Note: This panel does not allow you to configure inferred pressure compensation. Inferred pressure
compensation will be supported in a future release.
Configuration and Use Manual
system at www.expert2.com. To determine if your sensor requires pressure
2
Comments
This is a calculated value. Specify
the point that holds the result of
the calculation.
Read only.
Default: Flow Dependent Linear.
"No measurable flow" is defined by
the value specified for Low Flow
Cutoff (see Section 5.4.1).
Formulaic methods tend to
produce slightly lower averages
than do linear methods.
Flow-weighted methods produce
minute and hourly values that are
more reflective of short periods of
high flow.
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