Rice Lake Survivor 390HE Hostile Environment Digital Indicator - Manual (Page 40)

36 SURVIVOR 390HE 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
effective value for the DFSENS parameter.
8.7 Test Mode
In addition to normal and setup modes, test mode
provides a number of diagnostic functions for the
390HE, including:
• Display raw A/D count
• Set A/D offset and gain calibration
• 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.
A/D calibration functions, ADOFFS and
ADGAIN, must be used only by qualified
service personnel, and only after
replacing A/D converter components. Improper A/D
calibration may render the indicator unusable.
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 37 summarizes the test menu
functions.
Figure 8-5. Test Menu
Caution
A/DTST TEST PRTCFG DEFLT