Emerson AMS Wireless Vibration Monitor User Manual page 40

Configuration
August 2020
When the update rate is greater than 1 hour, the device will publish the last measurement
every hour (meeting the HART requirement to at least publish data once / hour) and will
publish the new data set on the update rate.
Reducing the update rate minimizes power consumption and extends the life of the
battery.
Note
If the device is configured to publish at the fastest allowable update rate (once per
minute), the battery is expected to last only about 2-3 months.
2.6.5 Alert levels
The AMS Wireless Vibration Monitor sets HART status bits to indicate when measured
values exceed the configured thresholds. Measured values have six levels: Saturated,
Sensor, Range, Advisory, Maintenance, and Failed.
The level at which these thresholds should be set depends on the type of equipment being
monitored and on your specific process.
Check the alert thresholds in
One rule of thumb for vibration is to examine the current level at which the equipment is
operating. Assuming the equipment is in good working condition, set the Advisory level at
2x the current value (or at a minimum of 0.05 in/s RMS, whichever is greater), set the
Maintenance level at 4x the current value, and set the Failed level at 8x the current value.
For example, if the current value for Overall Velocity is 0.1 in/s, set the Advisory threshold
at 0.2 in/s, the Maintenance threshold at 0.4 in/s and the Failed threshold at 0.8 in/s. While
this type of vibration program is not recommended, it can provide a starting point when
no other information is available.
A good rule of thumb for establishing the PeakVue alert levels is to use the rule of 10's. This
applies for most rolling element bearing equipment with a turning speed between 900
and 4000 CPM. Using this approach, the Advisory alert would be set at 10 g's, the
Maintenance alert at 20 g's, and the Failed alert at 40 g's. In general, PeakVue alert levels
can then be interpreted as follows:
10 g's
20 g's
40 g's
For more information on PeakVue, see PeakVue.
Notes
When any measured process parameter (Velocity, PeakVue, or Temperature) exceeds the
configured Advisory, Maintenance, or Failed threshold, this causes an alert indication that
you can view from AMS Device Manager (or in another graphical host). This indicator itself
does not set a status bit.
2.6.6 Trend parameters
You can trend parameters in multiple locations such as in a plant historian or in AMS
Machine Works. The method for configuring this functionality is contained in the
40
Device variable alert
Indication of Abnormal Situation
Serious Abnormal Situation - Maintenance Plan Required
Critical Abnormal Situation - Implement Maintenance Plan
limits.
MHM-97927-PBF, Rev 1
User Guide
MHM-97927-PBF