This device permits the non-destructive testing of multiple steel wire ropes; it is composed of two connected moduli (1, 2); each modulus (1, 2) has at least one magnet (5), at least one coil or more permanent magnets (5), one or more coils (7, 7.1), one signal power point (8), two rollers (14) and a shell; the shell is composed of two lateral plates (9), an upper plate (10), a lower plate (11), a fore plate (12) and a back plate (13); the magnets (5), fixed to the upper plate (10) and the lower plate (11), form with these pole pieces a magnetic inductor; the magnets (5) are placed on one or more planes, parallel to the plane of the multiple wire ropes (6); any discontinuity of the moving wire ropes (6) creates perturbations of the magnetic field, generating electric power which is transferred to an analogical recorder; this recorder can amplify it and print on paper the diagram showing the state of the wire ropes (6).