USER MANUAL
STM 550 / EMSI
–
ENOCEAN MULTISENSOR FOR IOT APPLICATIONS
© 2020 EnOcean | www.enocean.com F-710-017, V1.0
STM 550 / EMSI User Manual | v1.3 | September 2020 | Page 85/97
11.3.2
Device acceleration use cases
If an object vibrates or is moved after being, then the acceleration vector measured by the
acceleration sensor will change. Figure 65 below illustrates this.
Figure 65
–
Acceleration vector changes based on motion or vibration
This principle can be used for two major use cases:
◼
The approximate location of an object can be tracked based on the strength of the
received periodic data telegrams. Movement of the object (e.g. from one room to
another) can be detected based on the reported acceleration vector change.
◼
The utilization of an object
(a machine that is running, a chair that is occupied, …) can
be tracked based on the characteristic vibrations associated with this utilization.
In both cases, STM 550 should be attached to the object for which location or utilization shall
be monitored. The following chapter gives general guidelines how to do so.
11.3.3
Installation suggestions
The following points should be considered to maximize the reliability of acceleration meas-
urement:
•
STM 550 should be firmly attached to the asset without any damping to ensure that
any vibration of the asset will be properly propagated to STM 550
•
STM 550 should be attached to the asset at the location where the vibration is max-
imized. For instance, when tracking the utilization of office chairs, the highest accel-
eration is typically observed at the back rest.
•
The acceleration threshold for wake-on-acceleration should be selected such that uti-
lization / motion is reliably detected without false triggers due to spurious vibration
(e.g. people walking by)
•
Should the default sensitivity be insufficient even at the lowest threshold then the
sampling rate should be increased
Use acceleration test mode as described in chapter 2.2.6 to verify correct installation.