User's Manual

Table Of Contents
Issue Potential solution
The measured amplification
factor is greater than six.
The cause may be a rotational frequency close to a resonance that is
amplifying the vibration. Check the resonant frequencies. Slight
changes in weight size and location cause dramatic changes in the
apparent degree of imbalance.
Correction weights do not
reduce vibration at all
positions by a factor of three
or more.
The expected improvement based on the current influence
coefficients is marginal. The cause may be the variability of the data
being greater than the amount of the desired improvement.
Correction weights on trim
runs cause readings at some
locations to increase while
others decrease.
You may have reached the accuracy limits of the current influence
coefficients. Substitute the next to the last trim run for the original
reference run, and the last trim run data as trial run 1. Enter the last
trim weight as the trial weight. Calculate a new correction weight
and compare it with the last trim run calculation.
The precision can also be limited by the degree of random
variability in the data or due to non-linearity inherent in the
equipment.
Small modifications (1 to 2
percent) in the measured
data produce large changes
(20 to 30 percent) in the
calculated solution.
The trial weights did not cause enough change to create accurate
influence coefficients. Repeat the trial run and add enough weight
to achieve at least a 30 percent change in the resulting vector. The
phase and/or magnitude should differ from the reference by 10
percent or more.
Inconsistent results occur
using independent solutions
in the horizontal and vertical
directions.
The system is not responding linearly in the radial directions. The
cause may be the horizontal having a different resonant frequency
from the vertical.
9.16.6 Troubleshooting tachometers
Message Cause
Waiting for Trigger You lost the signal from the tachometer.
Tachometer Timeout No tachometer signal is present.
Tach Not Stable The tachometer readings vary by more than six percent between
revolutions.
9.17 Balance accessories
Contact your sales representative for a complete listing of the available accessories. The
accessories listed below highlight a few of the balancing accessories.
Balance
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DRAFT