Vibration Sensor
A vibration sensor (typically an accelerometer or velocity sensor) measures the oscillatory motion of rotating machinery to detect developing faults like imbalance, misalignment, or bearing wear before catastrophic failure occurs. It converts mechanical motion into an electrical signal representing parameters such as RMS velocity, peak acceleration, or frequency spectra.
In shop floor maintenance, vibration sensors are mounted as close to bearings as possible to capture accurate fault signatures, with measurements taken in three directions (horizontal, vertical, axial) to fully characterize vibration vectors. Integrated into CMMS platforms like ServiceGrid, sensors feed continuous or periodic data to predictive maintenance algorithms that identify trends, trigger alerts when thresholds are exceeded, and schedule corrective actions. Systems often trend RMS velocity for general machine health and peak acceleration for early bearing wear, enabling proactive maintenance and reducing unplanned downtime.
Which sensor type is best for early bearing wear detection?
Piezoelectric (PE) accelerometers are preferred for industrial condition monitoring due to wide frequency response, high signal resolution, and long-term stability at high temperatures, though MEMS capacitive accelerometers (e.g., ADXL335/345) are increasingly used for cost-effective continuous monitoring with integrated ADCs.
What frequency response rule should be applied?
Select a sensor with a maximum frequency response at least 3 to 4 times the highest fault frequency of interest (e.g., GMF for gearboxes, BPFO/BPFI for bearings) to capture harmonics crucial for accurate diagnosis.
How are faults classified from vibration data?
By capturing time waveform data and performing spectral analysis to identify specific frequencies (e.g., imbalance at 1× RPM, misalignment at 2× RPM, bearing defects at BPFO/BPFI) and correlating amplitude trends with failure modes.