The extremely power saving RF transmitter module STM 31x of EnOcean enables the realization of a wide range of wireless and maintenance free sensors such as temperature sensors, humidity sensors, or room operating panels. 

Functional Principle

Power supply is provided by a small solar cell, an external energy harvester, or an external 3V battery. An energy storage element is installed to bridge periods with no supply from the energy harvester. The module provides a user configurable cyclic wake up.After wake up a radio telegram will be transmitted in case of a change of any digital input value compared to the last sending or in case of a significant change of measured analogue values.In case of no relevant input change a redundant retransmission signal is sent after a user configurable number of wake-ups to announce all current values. In addition a wake up can be triggered externally.The firmware can be configured. Customer specific firmware can be developed using the Dolphin API.