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SKF Machine Condition Advisor
User
Manual
location (moving the probe only a few inches can
produce drastically different vibration readings). To
ensure measurements are taken at the exact same
spot, mark the measurement POINT with permanent
ink, machine a shallow conical hole with a drill point,
or use SKF’s adhesive measurement disks.
Acceleration enveloping measurements (bearing
vibration measurements) are especially sensitive to
sensor location. The optimal measurement location
for enveloped acceleration measurements is in the
bearing load zone, as close to the measured bearing
as possible. If the probe is positioned out of the load
zone or too far from the measured bearing, the
measured signal degrades in amplitude and appears
as a lower (and inaccurate) value.
Therefore, when measuring a bearing on a horizontal
shaft with a split bearing housing, you should perform
measurements on the housing’s lower portion (in the
load zone) when possible. This allows the overall
velocity vibration and acceleration enveloping
measurements to be simultaneous and accurate.
¾
Use the external sensor with magnet
attachment to increase the
consistency and quality of your
MCA’s vibration measurements.
Also, magnetic mounted sensors
provide higher sensitivity to vibration
signals occurring at higher
frequencies (i.e., bearing fault
vibration) than do probe tip sensors.
Thus, use the external magnetic
mounted sensor to facilitate earlier
