It is possible to replace an existing Bticino videophone with a Classe 300EOS with Netatmo: - in a single-family home: replacement without modification of the wiring of the indoor video monitor with a Classe 300EOS with Netatmo - in a multi-family building: depending on the characteristics of the installation, a simple replacement of the indoor video monitor with a Classe 300EOS with Netatmo may be sufficient or it may be necessary to add a dedicated power supply reference 346020 to each Classe 300EOS with Netatmo depending on the number of Classe 30EOS with Netatmo stations present in the installation. For the sizing of collective installations, refer to the General installation rules of the Technical Guide for 2-wire BUS installations. https://docdif.fr.grpleg.com/general/ouidoo/pdf/legrand-guide-technique-portiers-controle-dacces.pdf