Page 80 - Condition Monitor User Manual

Configuring a Monitor

Press the ‘Acquire Data’ button. The application will connect to the Guard and get a
fresh set of shaft trigger data. Once the data is collected, the graphs and the statistical
information will update:

• The red trace at the top of the graph is the signal that the monitor uses to synchronize
the data acquisition. If this signal is not stable, then the Shaft Trigger Threshold
should be adjusted, and a fresh set of Shaft Trigger data collected.
• The blue trace in the graph is the raw data collected from the Shaft Trigger.

• The black line on the graph is the trigger threshold.
• Information about the signal stability is displayed in the bottom of the screen.

Adjust the trigger threshold to an appropriate level, and then acquire data again. When
setting the Shaft Trigger level, use the following guidelines:

• Stay away from the top and bottom edges of the Shaft Trigger waveform. When
close to the edges, a slight variation can cause the system to miss Shaft Trigger
pulses.
• Set the threshold at a part of the signal that is more vertical (changing rapidly) rather
than a part of the signal that is more horizontal (changing slowly). When Triggering
on a slowly changing signal, this may introduce jitter and susceptibility to signal
noise.
• Stay away from any area where there is noise on the signal. If noise passes through
the trigger threshold, it could cause extra Trigger pulses to occur.
If the rotation speed is reported as stable and at the proper speed, then configuration is
complete. Otherwise, continue adjusting the trigger threshold and re-acquiring data until the
results are good.
There are some additional controls that may help find the appropriate trigger level:
• The zoom controls can be used to zoom in on the waveforms to get a better idea of
what the Shaft Trigger signal looks like.
• The ‘Automatically scale voltage’ checkbox will automatically adjust the vertical scale
of the Shaft Trigger signal so that it is easier to set a good trigger level, and easier
to see any voltage fluctuations in the signal.

• The ‘Find Trigger Level’ button will run a series of measurements to set the trigger
level automatically, although realistically it will be faster to do it manually.

7.5.6. GuardII+ Flux Measurement Configuration

Press the ‘Flux Measurement’ button on the ribbon to configure the Flux measurement.
The Flux Measurement configuration is split up into 2 main areas:

• The Flux graph shows the raw Flux signal and the integrated/analyzed signal.
• The controls are used to manually acquire a fresh set of Flux data and magnify the
graph if needed.

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