Iso 10816-3 Pdf Link

The standard divides machines into (I to IV) based on structural flexibility, foundation rigidity, and machine size. It then assigns vibration severity zones (A, B, C, D) for each class, where:

The standard recommends measuring vibration on the bearing housing or on the machine casing, using a velocity transducer or an accelerometer. iso 10816-3 pdf

Includes electric motors, generators, rotary compressors, blowers, fans, and steam turbines up to 50 MW. The standard divides machines into (I to IV)