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10.4 Conversion Factors for Secondary Units
The 380 has the capability to mathematically convert a weight into another unit of measurement and display the result with the
press of the Units key. Available units are pounds (lb), kilograms (kg), tonnes (t), grams (g), short ton (tn) and onces (oz).
Secondary units can be specified on the Format menu using the SECNDR parameter.
Multipliers are preconfigured within the indicator.
Note
Ensure the secondary decimal point position is set appropriately for the scale capacity in the secondary units.
10.5 Digital Filtering
Digital filtering is used to create a stable scale reading in challenging environments. The 380 allows selection of Digital Rolling
(Section
10.5.1) or RAW (no filtering). See
Average Filtering
location of FLTCHN parameter.
The scale's sample rate effects all types of filtering. The A/D sample rate is selected by the SMPRAT scale parameter. The A/D
sample rate is the number of weight readings the indicator takes per second (SMPRAT). This can be 5, 6, 10, 12, 20, 25, 40, 50,
80, or 100 hertz (readings per second). Set the A/D sample rate to the lowest setting required for the application. Lower settings
result in better stability.
10.5.1 Digital Rolling Average Filter (AVGONLY)
The digital rolling average filter uses mathematical averaging with three stages. These configurable stages control the effect of
a single A/D reading on the displayed weight. When an A/D reading outside of a predetermined band (defined by the DFSENS
and DFTHRH parameters) is encountered, the digital rolling average filter is overridden and the display jumps directly to the
new value.
Digital Filter Stages (DGFLTR1-3)
The filter stages can each be set to a value of 1–256. The value assigned to each stage sets the number of readings received
from the preceding filter stage before averaging. Setting the filter stages to 1 effectively disables the rolling filter.
A rolling average is passed to successive filtering stages for an overall filtering effect which is effectively a weighted average of
the product of the values assigned to the filter stages (DGFLTR1 x DGFLTR2 x DGFLTR3) within a time frame corresponding to
the sum of the values (DGFLTR1 + DGFLTR2 + DGFLTR3).
Digital Filter Sensitivity (DFSENS) and Threshold (DFTHRH)
The rolling averaging filter can be used by itself to eliminate vibration effects, but heavy filtering also increases settling time.
The DFSENS and DFTHRH parameters can be used to temporarily override filter averaging and improve settling time.
• DFSENS specifies the number of consecutive A/D readings which must fall outside the filter threshold (DFTHRH) before
filtering is suspended
• DFTHRH sets a controlling threshold delta value, in display divisions; the indicator monitors both the incoming filtered
and unfiltered A/D values; DFTHRH is the maxim allowable difference between the filtered and unfiltered A/D values for
which the filter will remain engaged; filtering is suspended when the difference between the filtered and unfiltered A/D
values is greater than the DFTHRH value for more than the specified number (DFSENS) of consecutive readings;
filtering is reengaged when two consecutive A/D readings are within the DFTHRH threshold delta value; Set DFTHRH to
NONE to turn off the filter override
Section 4.3.1 on page 23
© Rice Lake Weighing Systems ● All Rights Reserved
for configuration menu layout and the
Appendix
47
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