ISO 10816-3 Vibration Severity Evaluation

Vibration is the most direct indicator of a rotating machine's condition: the lower it is, the healthier the machine; excessive vibration means bearing wear, rotor unbalance or loose foundations are developing. ISO 10816-3 (equivalent to GB/T 6075.3) specifies limits for machines of different power and support type and divides machine condition into four zones, A to D, from newly commissioned machines to vibration severe enough to cause damage.

In practice, classification takes several steps: convert the measured acceleration to the RMS velocity required by the standard, find the limit table for the machine power and support, and compare zone by zone. The module automates this. Connect the sensor, select the machine group and the zone appears immediately, with the limits shown as colored zone charts.

Screen layout

Zones

If the RMS value exceeds the top of the chart, the value is shown in the top zone and does not leave the chart.

Supporting functions

Stay on top, print the evaluation screen, refresh for the current group and channel, open the built-in help, and Chinese or English interface following the main system.

Why RMS velocity

ISO 10816-3 evaluates machine vibration by the RMS value of vibration velocity in mm/s. Velocity reflects vibration energy directly and represents the overall condition of a machine better than displacement or acceleration alone; the RMS value averages the energy over time, resists occasional disturbances and is stable and repeatable.

From acceleration to velocity

Most vibration sensors output acceleration. Mathematically, velocity is the integral of acceleration, but direct integration amplifies low-frequency drift and integrates noise into large values. The module uses frequency-domain integration:

1. Decompose the acceleration waveform into its frequency components (spectrum analysis).
2. Divide the amplitude of each component by its angular frequency (2π × frequency), which converts acceleration to velocity at that frequency.
3. Combine the converted components into the velocity waveform.

The process runs only in the 10–1000 Hz band specified by the standard, so drift and high-frequency noise outside it are excluded. Window amplitude correction compensates the small amplitude reduction caused by analyzing a section of the signal, so the reading matches the true vibration.

From value to zone

The RMS velocity is compared with the limits of the selected group, and the zone it falls in is the result. The limits for all eight combinations are built in, so no manual lookup is needed.

The standard groups machines by power and support and gives zone boundaries for each group (mm/s RMS):

The pump groups and their limits are also built in according to the standard. Values below the A/B boundary are zone A, and so on; values above the C/D boundary are zone D.

• All ISO 10816-3 / GB/T 6075.3 limits built in; the zone appears after measurement without manual lookup.
• Eight evaluation groups side by side for comparison.
• Green, yellow, orange and red zones that non-specialists can read.
• Automatic bold frame on the zone containing the value.
• A standard accelerometer is sufficient: built-in frequency-domain integration converts to the velocity required by the standard.
• Window amplitude correction for accurate readings.
• One-line conclusion in the title bar: machine group, value, zone and recommended action.
• Raw waveform on the same screen for traceability.
• One-step printing of the evaluation screen.
• Practical details: stay on top, values beyond range stay in the top zone, automatic data validity check with a clear message.
• Chinese and English interface.

1. Select the machine group by rated power and support type (rigid or flexible).
2. Select the channel with the sensor connected.
3. Read the result in the title bar, or from the color of the framed zone.
4. Check that the acceleration waveform shows no clipping or obvious interference.
5. Print the evaluation screen if a record is needed.

Rigid or flexible support

Determine the support classification from the applicable standard and the machine/support dynamic characteristics, using documented design or modal evidence. Do not classify a running machine by pressing on its bearing housing. If the classification is unknown, withhold the zone conclusion until it is established.

Example

Hypothetical arithmetic example: if a machine is correctly classified as group 2 on rigid support and the applicable boundaries are 1.4 and 2.8 mm/s, a reading of 1.464 mm/s falls between them. The source example has conflicting support and zone labels, so this is not a verified classification of that machine or an operating authorization.