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USER MANUAL
STM 550X / EMSIX
–
ENOCEAN MULTI-SENSOR
© 2020 EnOcean | www.enocean.com F-710-017, V1.0
STM 550x / EMSIx User Manual | v1.0 | February 2020 | Page 76/79
In addition to that, the following points should be considered to maximize the reliability of
utilization tracking:
•
STM 550x should be firmly attached to the asset without any damping to ensure that
any vibration of the asset will be properly propagated to STM 550x
•
STM 550x 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
9.3
Temperature and humidity measurement
The dedicated temperature and humidity sensor integrated into STM 550x accurately
measures and reports temperature and humidity present at its surface. To achieve the best
possible accuracy, it is important to consider the following points:
◼
Installation height
The sensor should be installed at a height that is representative for the use case. For
the case of an office, the sensor should be mounted at desk level.
◼
Sun light or heat exposure
The sensor should be mounted such that it is not directly exposed to sunlight or heat
(e.g. close to a radiator)
◼
Disturbances
The sensor should be mounted such that the influence from disturbances such as the
air stream from air condition units is minimized. Consider also the possible tempera-
ture gradient between wall and room when mounting the sensor directly onto a wall.
◼
Air flow
The sensor should be mounted such that the airflow from the target measurement
area towards the air inlets is maximized. This will ensure the lowest possible response
time of the sensor. Avoid mounting the sensor in niches or slots with little air flow.
When designing your own housing around an STM 550x module, consider the location
of the ventilation slots (there are four of them in total) as shown in Figure 2 and
maximize the airflow towards them.