A small radial/axial settlement of

A small radial/axial settlement of the blades can occur during the test. The checks described in paragraph 4.1 of ITN07202 must be performed for this reason. 7.5. Low Speed Balancing Check after Over Speed Test After the Over Speed test, a low speed balancing check with shall be performed and recorded on test plan document. 7.6. Influence of the driving coupling check The driving coupling influence check shall be performed before rotor High Speed Balancing. Rotor vibrations shall be recorded for a ramp up to trip speed and successive coast down (“reference run”). The driving coupling shall be 180 degrees rotated and the ramp up to the trip speed shall be repeated (“rotated drive assembly run”). The rotor vibrations shall be recorded and the vectorial difference between the two ramps shall be computed (“drive assembly influence”). The computed drive assembly influence shall be compared with the balancing tolerances given in table 1, shown in the following paragraphs. The drive assembly influence check is considered passed if the computed drive assembly influence is below the 25% of the tolerance given in table 1.