Acceptable fan vibration level for single operating fan
The manufacturer has tested the vibration levels of the installed fans at the factory. The
measurement point is near the bolt for motor support/collar end, shown in Location for vibration measurement. The limits for site vibrations
are presented in Vibration limits of fan. A sudden
change in the vibration level may indicate the need for prompt inspection or maintenance. Do
not use transitory changes in vibration level that result from relubrication or maintenance
for evaluating the condition of the fan. The vibration sensor is optional for fans.Figure: Location for vibration measurement
The vibration limits of the fan for a test conducted at site depend on the selected reference
measuring point. At site, the reference point for outside measurement is in the leg near the
fan. Always use the same measurement point or points.
