FIELD: monitoring and measuring processes and devices for contact free measuring and continuous monitoring of oscillation amplitude of turbine and compressor blades at operation. SUBSTANCE: method comprises steps of mounting two peripheral pickups on housing of turbomachine; registering time moments of passing peripheral section of blade near pickups spaced by basic distance in circumferential direction; measuring time intervals of passing i- blade from first pickup until second pickup, between said pickups; measuring mean value (during respective measured time intervals), linear velocity values of motion of peripheral section of i-blade; calculating pitch difference of first blade at multiplying measured time intervals by mean (during respective measured time intervals) linear velocity values of motion of peripheral section of i-blade and extracting from each multiplication result value of basic distance between pickups; collecting statistical set of pitch difference values of i-blade in order to define difference between maximum and minimum values of pitch differences of i-blade; according to difference between maximum and minimum values of pitch differences received for i-blade evaluating oscillation amplitude. EFFECT: lowered error degree at determining amplitude oscillations of turbomachine blade. 1 cl
