FIELD: winding of coiled materials. SUBSTANCE: method for measuring diameter of coiled material comprises steps of rotating reel, detecting at least twice time moment when predetermined point of coiled material passes through preliminarily set position and determining time interval between two passes or rotation angle value of supporting shaft; calculating diameter of coil with use of time interval, circumference velocity of reel, rotation angle and radius value of supporting shaft. EFFECT: enhanced accuracy of measurement. 18 cl, 9 dwg
