Free Engineering Tool
Vibration Acceleration Calculator (ISO 20816)
Convert vibration velocity (mm/s RMS) to acceleration (m/s², g) at any frequency. Enter velocity and frequency to get acceleration RMS, peak, and displacement results.
Results
Acceleration from Velocity
For sinusoidal vibration, acceleration is derived from velocity by multiplication with angular frequency:
Conversion to g
Displacement from Velocity
Where:
- vRMS — vibration velocity RMS (mm/s)
- f — frequency (Hz); if RPM given: f = RPM / 60
- aRMS — acceleration root mean square (m/s²)
- apeak — acceleration peak = aRMS × √2 (m/s²)
- dpp — displacement peak-to-peak (μm)
Practical Example
aRMS = 4.5 × 2π × 25 / 1000 = 0.707 m/s²
apeak = 0.707 × √2 = 1.000 m/s²
ag,RMS = 0.707 / 9.80665 = 0.072 g
dpp = 4.5 × √2 × 1000 / (π × 25) = 81.0 μm
Vibration Parameter Comparison
| Parameter | Best Frequency Range | Typical Units | Primary Use |
|---|---|---|---|
| Displacement | < 10 Hz (600 RPM) | μm p-p | Low-speed machines, shaft vibration |
| Velocity | 10–1000 Hz | mm/s RMS | General machine condition (ISO 10816) |
| Acceleration | > 1000 Hz | m/s², g | Bearing defects, gear mesh, high-freq |
Vibration acceleration is the rate of change of vibration velocity, measured in m/s² or g (where 1 g = 9.80665 m/s²). It is the most sensitive parameter to high-frequency vibration and is critical for detecting bearing defects, gear mesh faults, and other high-frequency mechanical problems.
Acceleration increases with both vibration amplitude and frequency, making it the parameter of choice for frequencies above 1000 Hz.
Acceleration is preferred for high-frequency vibration analysis, typically above 1000 Hz. It is the best parameter for early detection of rolling element bearing defects, gear mesh problems, and cavitation.
Velocity (mm/s RMS) remains better for general machine condition assessment in the 10–1000 Hz range per ISO 10816 / ISO 20816. Many modern monitoring systems use acceleration enveloping (demodulation) for bearing diagnostics.
To convert from g to m/s², multiply by 9.80665 (the standard acceleration due to gravity). For example, 0.5 g = 0.5 × 9.80665 = 4.903 m/s².
Conversely, to convert from m/s² to g, divide by 9.80665. The g unit is popular in vibration analysis because typical industrial vibration levels fall in a convenient numeric range — roughly 0.01 to 50 g.
Piezoelectric accelerometers are the standard sensors for vibration acceleration measurement. IEPE (ICP) type accelerometers with integrated electronics are most common in industrial applications, offering wide frequency range (0.5 Hz to 20+ kHz), high sensitivity, and excellent durability.
MEMS accelerometers provide lower-cost alternatives for monitoring systems. Charge-mode piezoelectric accelerometers are used in high-temperature environments above 120 °C.
Typical vibration acceleration levels depend on machine type, speed, and frequency. For general industrial machinery at operating speed:
- < 0.5 g — Good condition
- 0.5–2 g — Acceptable
- 2–5 g — Alarm level
- > 5 g — Investigate immediately
High-frequency bearing defect signals can reach 10–50 g peak. ISO 20816 primarily defines zone boundaries using velocity, but acceleration is essential for high-frequency diagnostics.
The procedures described on this page were developed and field-tested by the Vibromera team using the Balanset-1A, a portable dual-channel balancer and vibration analyzer for on-site rotor balancing.
Professional field balancing instruments with built-in vibration analysis, acceleration measurement, and ISO 10816 / ISO 20816 evaluation. Used in 50+ countries.
Nikolai Shelkovenko
Nikolai Shelkovenko is a vibration analysis engineer and the founder and CEO of Vibromera. For more than 15 years he has balanced rotating equipment in the field rather than on a test bench: mulchers, industrial fans, crushers, centrifuges, shafts and spindles. That work is what the Balanset instruments grew out of — they were designed as a tool a specialist can carry to the machine and use alone, on site, not as laboratory equipment. Vibromera was founded in 2017 and has been based in Porto, Portugal, since 2023. Development, assembly and support of the Balanset line all happen here. The flagship instrument is the Balanset-1A, a portable analyser for single- and two-plane balancing and for vibration diagnostics. Nikolai is personally involved in customer support, in working through difficult balancing cases and in the development of the software. He works with customers worldwide, in any language.
