Campbell Scientific CDM-VW300 Series Dynamic Vibrating-Wire Analyzer System - Manual (Page 62)

CDM-VW300 Series Dynamic Vibrating-Wire Analyzers
7.12.2.1
7.12.2.1.1
Monitoring with DVWTool Software
The Dynamic Vibrating-Wire Tool Box (DVWTool) is a software package that
enables a PC to communicate with the CDM-VW300 via USB (no datalogger
required), configure CDM-VW300 settings, and display the output of attached
sensors. The output data can be graphed on a line graph or in a rainflow
histogram. For more information, refer to Section 7.1.2, Using DVWTool.
Fault Detection
Fault indication are shown in FIGURE 7-18, Dynamic Vibrating-Wire Tool
Box Fault Indicators. A value other than 0x00 in the DVWTool Diagnostic
Bits field indicates a fault. The fault is emphasized by measurement results
appearing in red type, as illustrated in the following figure. Occasionally, the
display of the measurement values will also be flashing. A fault is
accompanied by an information icon (i inside a blue circle) in the Diagnotic
Bits field. Click on the i to view a short decription of the fault. An argument
input error is indicted by a red field and a ! inside a yellow triangle. Click on
the ! to view a short description of the error.
When the frequency of a sensor changes quickly (corresponding to rapid
changes of the phenomenon under test), the energy in the vibrating wire may
drop briefly until the excitation mechanism can insert energy at the new
frequency. The result is that a low-amplitude diagnostic condition may appear
for a short time. This is expected behavior. Low- and high-amplitude
diagnostic codes that appear briefly are usually no cause for concern. For these
instances, there is no loss of fidelity in the values measured by the analyzer.
However, low- and high-amplitude diagnostic codes that occur for long
continuous periods require investigation.
See Section 8.5, Diagnostic Outputs, for more detail about the faults that are
displayed in the Diagnostic Bits field.
FIGURE 7-18. Dynamic Vibrating-Wire Tool Box Fault Indicators
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