In Engineering practice one of the most common devices used to control horizontal displacements are the inclinometers embedded in structures or soils, depending the purpose of the study. The diaphragm walls of the new Metronorte line were instrumented, in the framework of the Expansion and Development Program of the Madrid Underground in Spain, from 2003 to 2007. The data of displacements was collected in several field measurements. This data was procesed, analyzed and interpreted, focusing in the posible sources of error all this with the Unit of Control (USAC) of MINTRA. This article summarizes the main results obtained from the field displacements in diaphragm wall in Madrid.