@kalina, Thanks. So it will not work for my configuration. Wall switch (push button) is already installed. No possibilities to draw more electrical wires. Moreover, if i put the board near the light, i have just the Neutral and the return wire from the wall switch. No Live wire to power on the mysensors board. I think in my ase the best way is to manage everything in my garage in the electrical main board where all the wires are mapped. I can get L + N for mysensors power supply. And i can continue to reuse the original wall switch independently of the Mysensors board.