User's Manual

3. Enter the weight and location of the trial weight into the Estimate Trial Weights
screen.
4.
Start the equipment.
5. Acquire data at all measurement points and speeds.
6. Repeat these steps for each trial run in your job.
Where to place the trial weights
Trial weights determine the effect on the equipment when you add or remove a known
weight at a known location. Change the weight so you get a significant change in data
from the reference run, without increasing the vibration levels. You want to cause at least
a 30 percent change in magnitude and/or phase compared to the reference run.
The Balance program has trial weight estimation function you can use to help you select a
trial weight. Estimate Trial Weights in Calculator Mode calculates a trial weight that reduces the
vibration levels in the reference run. The analyzer uses the reference run and physical data
for the rotor for this calculation.
When you add weights to a single weight plane, use the same radius from the center of the
shaft. The weight and the radius determine the net effect. For example, a 5 oz. weight
placed at 10 in. has double the effect of a 5 oz. weight placed at 5 in. (50 oz.-in. versus 25
oz.-in.).
Although the setup is not typical, you can place weights at up to two locations in any
weight plane. You can also place weights in other weight planes.
Keep or remove trial weights
You can keep or remove the trial weights from the previous plane. If you keep the trial
weight and add more weight, you must enter both weights into the table for the trial
weight amounts. If you place weights at different radii on the same weight plane, this must
be considered when entering trial weight data or placing correction weights. If the weights
for a single weight plane are all at the same radius, you need only consider the weight
units.
Acquire trial run data
CAUTION!
Follow proper safety and equipment lock out procedures when working around rotating
equipment. Acquire data from the specified location for the highlighted measurement point. If
you assign data from other measurement points to this location, you invalidate all calculations.
Prerequisites
• Complete or review the Job Setup option.
• Ensure the machine is shut down.
Balance
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DRAFT