Main Drive Motor

Both the motor inboard and outboard acceleration and velocity overall trends gradually increased into severe amplitudes. The motor outboard Y axis exceeded 20 g’s. The motor outboard Y axis vibration spectrums showed indications of suspected soft foot and looseness, with electrical frequencies visible throughout both velocity and acceleration spectrums. Aside from induced electrical frequencies into the sensor, first suspicions are there might be soft foot of misalignment developing.

A SENTRYsolutions Analyst ensured the motor inboard bearing was well lubricated and there was nothing rubbing on the rotating elements. They also verified the NU240 C3 bearing on non-drive end and replaced the motor bearings.