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 15/79
2.4
Reporting interval
STM 550x will transmit its status as data telegram at a regular interval, the so-called report-
ing interval. By default, the reporting interval is 60 seconds, i.e. STM 550x will measure and
report its status approximately once per minute.
STM 550x is designed to apply fluctuations up to +-10% to any configured reporting interval
to increase transmission reliability and meet regulatory requirements.
If STM 550x is configured to report acceleration, then it will always report the initial acceler-
ation detection after a period without detected acceleration immediately. Likewise, if STM
550x is configured to report magnet contact status, then it will report any change in the
status of the magnet contact sensor (open -> closed or closed -> open) immediately.
2.4.1
Energy considerations
The default reporting interval of 60 seconds (one update per minute) is adjustable using the
NFC interface as discussed in the subsequent chapters. The minimum possible reporting in-
terval is 3 seconds and the maximum possible transmission interval is 65535 seconds.
Lowering the reporting interval of STM 550x will increase its power consumption since it will
measure and transmit more often. Likewise, increasing the reporting interval of STM 550x
will reduce its power consumption since it will measure and transmit less often.
To select the right reporting interval, it is essential to determine the amount of harvestable
energy. STM 550x harvests energy from the available ambient light; therefore, the amount
of available energy is determined mainly by the intensity of the available light and the amount
of time during which the light is available.
The amount of available ambient light can be determined by executing an illumination test
as described in chapter 2.3.5. The light availability period (the time during which the ambient
light is available) has to be determined based on the lighting scheme used for the environ-
ment where STM 550x is installed.
STM 550x is designed to provide one update per minute based on 200 lux of ambient light
available for 6 hours per day. The minimum supported update interval for self-supplied op-
eration based on other conditions is summarized in Table 2 below.
6 hrs / day
8 hrs / day
10 hrs / day
12 hrs / day
50 lux
Not supported
Not supported
180 s
120 s
100 lux
120 s
90 s
90 s
60 s
150 lux
90 s
60 s
60 s
45 s
200 lux
60 s
45 s
45 s
30 s
300 lux
45 s
30 s
30 s
20 s
400 lux
30 s
25 s
25 s
15 s
500 lux
25 s
20 s
20 s
15 s
Table 2
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Minimum self-supplied reporting intervals
