How will the eccentricity be recorded?
In most cases, a reference cylinder will be aligned concentrically on the rotating positioning system and the outer surface of the reference cylinder scanned with a horizontal measurement probe. For the measurement, the positioning system will complete at least two full revolutions in order to record all periodic deviations.
The eccentricity is half of the peak value of the measured profile. The real profile can deviate from the ideal circular path in both negative and positive directions.
Installation location and load changes can have an influence on the amount of eccentricity.
The profile logged is averaged with an offset correction. The deviation from true running is half of the peak value of the averaged profile. The real profile can deviate from the ideal surface in both negative and positive directions.