Tracer AV
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6.6.3 Setting the Digital Filter Parameters
Fine-tuning the digital filter parameters greatly improves
Tracer AV
performance in heavy-vibration environments. Use the
following procedure to determine vibration effects on the scale and optimize the digital filtering configuration.
1. In setup mode, set all three digital filters (DIGFL1, DIGFL2, DIGFL3) to 1. Set DFTHRH to NONE. Return the Tracer
AV to normal mode.
2. Remove all weight from the scale, then watch the indicator display to determine the magnitude of vibration effects on
the scale. Record the weight below which all but a few readings fall. This value is used to calculate the DFTHRH
parameter value in Step 4.
For example, if a heavy-capacity scale produces vibration-related readings of up to 50 lb, with occasional spikes to
75 lb, record 50 lb as the threshold weight value.
3. Place the Tracer AV in setup mode and set the digital filters (DIGFL
x
) to eliminate the vibration effects on the scale
(Leave DFTHRH set to NONE). Reconfigure as necessary to find the lowest effective values for the DIGFL
x
parameters.
4. With optimum values assigned to the DIGFL
x
parameters, calculate the DFTHRH parameter value by converting the
weight value recorded in Step 2 to display divisions:
threshold_weight_value / DSPDIV
In the example in Step 2, with a threshold weight value of 50 lb and a display division value of 5 lb:
50 / 5 lb = 10 DD.
DFTHRH should be set to 10 DD for this example.
5. Finally, set the DFSENS parameter high enough to ignore transient peaks. Longer transients (typically caused by
lower vibration frequencies) will cause more consecutive out-of-band readings, so DFSENS should be set higher to
counter low frequency transients.
Reconfigure as necessary to find the lowest effective value for the DFSENS parameter.
6.7 Test Mode
In addition to normal and setup modes, test mode provides a number of diagnostic functions for the
Tracer AV
, including:
• Display raw A/D count
• Reset configuration parameters to default values
• A/D internal calibration
Test mode is intended for factory use only.
To enter test mode, press and hold the setup switch until the front panel display shows the word
TEST
. After about three
seconds, the test mode display automatically shifts to the first test menu function, A/DTST.
shows the Test Menu structure;
summarizes the test menu functions.
Figure 6-5. Test Mode Menu
TEST Menu
Function
Description
A/DTST
Display A/D test
Press and hold Enter key to display raw count from A/D converter.
DEFLT
Default parameters
Press setup switch and Enter key at the same time to reset configuration and calibration parameters to factory default values. Load
cells must be recalibrated before using the
Tracer AV
(see
).
Table 6-5. Test Mode Menu Functions
Note
A/DTST
TEST
ADOFFS
ADGAIN
DEFLT
