It is possible to replace the current Home + Security video unit with the Class 100X: - Villa or single & two-family context: replacement without modifying the video door entry system wiring - Condominium or multi-family context: depending on the characteristics of your system, it may be sufficient to replace the apartment station or it may be necessary to add a dedicated power supply cod.346020 For the sizing of multi-family systems, refer to the General Installation Rules of the 2-Wire System Technical Guide