Rice Lake Farm Bars - IQ plus 390-DC - Manual (Page 42)

38 IQ plus 390-DC Installation Manual
8.6.3 Setting the Digital Filter Parameters
Fine-tuning the digital filter parameters greatly
improves indicator 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 indicator 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 indicator in setup mode and set the
digital filters (DIGFLx) to eliminate the
vibration effects on the scale. (Leave
DFTHRH set to NONE.) Reconfigure as
necessary to find the lowest effective values
for the DIGFLx parameters.
4. With optimum values assigned to the DIGFLx
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 5D:
50 / 5D = 10. DFTHRH should
be set to 10DD 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
8.7 Test Mode
In addition to normal and setup modes, test mode provides a number of diagnostic functions for the IQ plus 390-
DC, including:
• Display raw A/D count
• Reset configuration parameters to default values
• Print indicator configuration
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.
Figure 8-5 shows the Test Menu structure; Figure 8-6 shows the front panel key functions in test mode. Note that,
because the Test Menu functions are all on a single menu level, the
GROSS/NET ( ) key has no function. Press
the ZERO ( ) key to exit test mode.
Table 8-5 on page 39 summarizes the test menu functions.
Figure 8-5. Test Menu
A/DTST TEST PRTCFG DEFLT