Vibration Chart Reference for Machinery Diagnostics

When it comes to maintaining the health of rotating machinery, vibration analysis is one of the most effective diagnostic tools available. But interpreting vibration data requires a clear reference framework — and that's where a vibration chart becomes essential. At STI, we provide advanced vibration monitoring solutions and tools to help maintenance teams quickly identify faults, assess equipment condition, and prevent unexpected failures using industry-standard vibration charts.

What Is a Vibration Chart?

A vibration chart is a visual guide that helps technicians and engineers interpret vibration levels in rotating equipment. It compares measured values (such as velocity, acceleration, or displacement) against industry benchmarks to determine whether machinery is operating normally or exhibiting signs of failure.

These charts are often color-coded with zones ranging from "Good" to "Dangerous," helping users instantly understand the severity of a vibration reading.

Key Vibration Measurement Units

Vibration can be measured in three primary units:

●     Displacement (mils or µm) – Often used for low-frequency issues like imbalance or misalignment

●     Velocity (in/sec or mm/sec) – Ideal for general machine condition monitoring

●     Acceleration (g’s or m/s²) – Best for detecting high-frequency faults like bearing damage

At STI, we offer sensors and transmitters that can output in any of these formats, allowing for flexibility based on your diagnostic needs.

How to Use a Vibration Chart

1.    Select the Correct Unit – Choose displacement, velocity, or acceleration based on the fault type you're monitoring.

2.    Compare Readings – Plot your sensor readings against the vibration chart reference to determine the condition zone (e.g., Good, Satisfactory, Unsatisfactory, or Unacceptable).

3.    Take Action Based on the Zone:

○     Good: No action required

○     Satisfactory: Monitor regularly

○     Unsatisfactory: Plan maintenance

○     Unacceptable: Immediate corrective action required

Common Fault Signatures on Vibration Charts

●     Unbalance: High vibration at running speed (1× RPM)

●     Misalignment: High vibration at 1× and sometimes 2× RPM

●     Bearing Defects: High-frequency acceleration spikes

●     Looseness: Broad-spectrum or harmonics in the velocity spectrum

With the help of a reliable vibration chart, technicians can link these signatures to specific mechanical issues, enabling faster, more accurate diagnostics.

STI’s Role in Vibration Monitoring

At STI, we provide:

●     High-quality vibration sensors and transmitters

●     Vibration switch systems for machinery protection

●     Expert support and training on how to use vibration charts for preventive maintenance

Our goal is to empower your maintenance team with the tools and knowledge to minimize downtime and extend the life of your machinery.

Looking for the right tools to interpret your vibration data?
 Visit www.stiweb.com to explore our full range of vibration monitoring products and request your free vibration chart reference guide today. With STI, smarter diagnostics lead to stronger operations.