Device for mechanically locating and reading the setting of an adjustable valve

Device for mechanically locating and reading the setting of an adjustable-pressure magnetic valve (v) for controlling the flow of a fluid in a predetermined direction (D), comprising a magnetic compass (10) and an alignment mark (21) for aligning the magnetic compass (10) with respect to the direction (D) in which the fluid flows through the valve (V), characterized in that the magnetic compass (10) comprises a reference plane (Pr) and a magnetic indicator (12, 42, 52) which is mounted such that it can pivot in all three dimensions of space under the effect of the magnetic field of the valve, the valve setting being represented by the angle (β) formed, in the reference plane, between the magnetic indicator (12, 42, 52) and the alignment mark (21) when the magnetic indicator (12, 42, 52) is positioned substantially perpendicular to the reference plane (Pr), the magnetic compass then being centered on the magnetic centre of the valve, and in that the magnetic indicator (12, 42, 52) is equipped with at least one magnet capable of receiving a magnetic field and having a north-south direction, the said at least one magnet being arranged in such a way that this north-south direction is substantially perpendicular to the reference plane (Pr) when the magnetic indicator (12) is positioned substantially perpendicular to the reference plane (Pr).