Emerson 2130 RBM Consultant Pro, Справочное руководство

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3-172 Horizontal Alignment
If enough data points were acquired, but they are displayed in a randomly scattered
pattern across the screen the measured misalignment amplitudes will decrease
while the ratio of noise to the signal increases. In this case, problems (e.g. a bearing
fault, a loose coupling, a rub, etc.) can distort the sine fit curve. This is the most
common reason for unfit sine fit curves. When this occurs, check the amplitudes of
each curve and edit the unfit sine fit curve to make it fit or change to the four point
method and acquire new data.
The peak-peak amplitudes of each sine fit curve can be used to determine whether
the laser heads are mounted on the shafts properly or if the machines are aligned.
If the amplitudes of both machines are around two mils or less and three or more
data points were acquired in a sweep arc of 45° or more the machines might pos-
sibly be aligned within tolerance. When this condition exists, the accuracy of any
further adjustments may be reduced using the available data.
If the peak-peak amplitudes of the sine fit curves are too high, check the sine fit
curve for data points which might lie far away from the sine fit curve and either edit
the sine fit and remove the measurement points which might lie far away from the
curve or change to a four point method and acquire new data. Another possible
reason for this condition could be the presence of too much looseness in the
system. To verify this condition, it will be necessary to check the system for looseness
and then repeat the measurement.
Display Sine Fit Function Keys
Delete/Undelete Point
Use the Delete/Undelete Point key to delete or undelete the selected point. The
point is not actually deleted from the data set, but it is marked (or unmarked) so
that it is not used when the program fits a sine wave to the data points. A deleted
point is not used in the fit calculation. Whenever points are deleted or undeleted
the fit is recalculated. A minimum of three points is required for the fit calculation.
Full Screen
Use the Full Screen key to display the plot in “full” screen mode. In full screen
mode, the soft keys disappear and only function to return the display back to its
original size.