USER MANUAL
STM 550B / EMSIB - EASYFIT MULTISENSOR FOR IOT APPLICATIONS (2.4 GHZ BLE)
© 2020 EnOcean | www.enocean.com
F-710-017, V1.0
STM 550B / EMSIB User Manual | v1.3 | June 2020 | Page 11 / 115
2
Functional overview
2.1
Product description
The energy-harvesting multi-sensor module STM 550B from EnOcean provides wireless sens-
ing functionality without batteries. Power is provided by an integrated solar cell. STM 550B
transmits sensor data using the 2.4 GHz Bluetooth Low Energy standard.
STM 550B operates fully self-powered (no batteries required) when sufficient available am-
bient light (200 Lux for 6 hours per day) is available. In this configuration it is fully mainte-
nance-free. For cases where sufficient ambient light is not available there is the option to
mount a CR1632 backup battery.
Radio telegrams transmitted by STM 550B are authenticated AES-128 security based on a
device-unique private key and a sequence counter. This ensures integrity and authenticity of
the transmitted telegrams and prevents telegram replay (retransmission of previously trans-
mitted telegrams).
2.2
Functional modes
STM 550B supports seven functional modes:
◼
Standard operation mode
◼
Standby (Sleep) mode
◼
Learn mode
◼
Function test mode
◼
Illumination test mode
◼
Acceleration
◼
Factory reset mode
Out of the box, STM 550B will be in standby mode to conserve energy during
transport and storage. Upon initial setup, STM 550B has to be set to standard op-
eration mode by pressing the LRN button shortly as described in chapter 11.1 or
via the NFC interface as described in chapter 9.5.17