4.5.2 Configure Density Damping
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Configuration
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Process Measurement
>
Density
>
Damping
ProLink III
Device Tools
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Configuration
>
Process Measurement
>
Density
>
Density Damping
Field Communicator
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Manual Setup
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Measurements
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Density
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Density Damping
Density Damping
controls the amount of damping that will be applied to density data.
Damping is used to smooth out small, rapid fluctuations in process measurement. The damping value
specifies the time period, in seconds, over which the transmitter will spread changes in the process variable.
At the end of the interval, the internal value of the process variable (the damped value) will reflect 63% of the
change in the actual measured value.
Procedure
Set
Density Damping
to the desired value.
•
Default: 1.28 seconds
•
Range: 0.0 to 60 seconds
Tip
•
A high damping value makes the process variable appear smoother because the reported value changes
slowly.
•
A low damping value makes the process variable appear more erratic because the reported value changes
more quickly.
•
The combination of a high damping value and rapid, large changes in density can result in increased
measurement error.
•
Whenever the damping value is non-zero, the damped value will lag the actual measurement because the
damped value is being averaged over time.
•
In general, lower damping values are preferable because there is less chance of data loss, and less lag time
between the actual measurement and the damped value.
•
If a number greater than 60 is entered, it is automatically changed to 60.
Effect of Density Damping on volume measurement
Density Damping
affects liquid volume measurement. Liquid volume values are calculated from the damped
density value rather than the measured density value.
Density Damping
does not affect gas standard volume
measurement.
Interaction between Density Damping and mA Output Damping
When the mA Output is configured to report density, both
Density Damping
and
mA Output Damping
are
applied to the reported density value.
Density Damping
controls the rate of change in the value of the process variable in transmitter memory.
mA
Output Damping
controls the rate of change reported via the mA Output.
Configuration and Use Manual
Configure process measurement
MMI-20048166
April 2019
Configuration and Use Manual
37