The present invention relates to a monitoring device (9) for an electric appliance (1), comprising electronic control means and data and/or information storage means. Said monitoring device (9) is typically connected to a first communication network (70A, 70B) through first interface means (7) and to a second communication network (80) through second interface means (8). Said first communication network (70A, 70B) is adapted to connect at least one sensing device (93, 94, 95, 96), being capable of measuring at least one value of at least one physical quantity related to the monitored electric appliance (1), to the monitoring device (9). According to the present invention, the monitoring device (9) receives the value of at least one physical quantity through the first interface means (7), and the electronic control means use said value of at least one physical quantity in order to obtain at least one piece of information related to the monitored electric appliance (1).