Alignment performed on 10,000HP Main Drive Motor with an 11ft spacer shaft at a steel mill. An overhead crane was used to rotate the shaft. A Rotalign Ultra iS was used on the alignment job.
Multi-point measurement mode was used and roughly 15 points were taken over 315 degrees of rotation. I used multi-point measurement mode because I was not sure if the crane pulling on the shaft would affect the results. Multi-point measurement takes points as the shaft is static. The crane moves the shaft to a new position and the tension is released. Then a new point is taken. This minimizes the shaft deflection and makes the reading more accurate.
It is important to have an alignment tool that recognizes spacer shaft tolerances. There was no problem keeping the laser on the sensor as we rotated the shaft because of the larger sensor plane. I was very happy with the alignment results.