Bob Assistant - Reference Manual
2023-04-04 - Version 1.0
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should not be taken into account.
On the other hand, if you notice many missing Report messages, we recommend adding a LoRa gateway
to improve LoRa network performance.
7.17.
BoB ASSISTANT did not detect any anomalies, however, a failure
occurred. What to do about it?
Check that BoB ASSISTANT has been positioned as close as possible to the vibration source. If your
machine has several sources of vibration, it may be interesting to place several BoB ASSISTANTs on the
equipment, especially on complex and bulky machines.
A wear or breakdown are almost always preceded or accompanied by a change in the vibration signature.
7.18.
What is the difference between alarm and notification?
An alarm is sent by BoB ASSISTANT when it detects an anomaly greater than 25%. This generic value was
determined after hundreds of thousands of hours of experimentation with the solution and corresponds to
the most common case: when the anomaly level reaches 25%, you should check your equipment.
However, each piece of equipment has its own vibration regime and adding notifications at the
application level based on report data allow you to customize the alert thresholds according to your
expectations and the criticality of your requirements. For more information on custom notifications, see the
following paragraph.
7.19.
How to configure a notification trigger threshold?
At the end of the learning mode the average abnormal vibration level is generally low (<10%). It is
advisable to wait 3 weeks to observe this average level, and to establish a notification threshold accordingly.
It is therefore recommended that the application receiveing BoB Assistant data fo vizualisation on a
dashboard also manages a notification system based on the average vibration drift level in reports.
Example :
In this case, the average abnormal vibration level is 5%. The variations observed may correspond to the
different phases of the machine (start-up, variations related to climatic conditions). A relevant alert
threshold for notifications on abnormal vibration level is 10%. In case of an alert, this does not mean that
your machine is in immediate danger but that vigilance is required.
You can also set up several notifications:
- 10% vigilance threshold
- 20% alert threshold (recommended physical intervention)
As a general rule, if a large number of notifications are received shortly after installation, the trigger
threshold at the application level is probably too low and should be raised.
7.20.
Why does the learning progress report indicate a value outside of
expected values (20%, 40%...)?
If the machine is stopped during the learning process, BoB ASSISTANT detects it and pauses the learning.
It will resume when the machine restarts.
However, if the machine stop exceeds a certain time, an activity report is sent (every 3 hours), indicating
the progress, which can be blocked between 2 standard values.
