The accelerometer (21) for measuring acceleration in a direction marked as G, consists of a printed circuit board (21) on which a sensor (24) is mounted. A substrate (22) is used as mounting plate at right angles to the circuit board with its plane parallel to G. The direction of acceleration measurement G is thus parallel to the plane of the circuit board and the substrate. The acceleration sensor consists of two piezo-electric sensors (31,32) which are polarised in the direction of acceleration measurement G.
