Roller bearings can be investigated during ongoing operation in order to determine their condition and to detect possible defects at an early stage. This is possible with a damage frequency analysis. The noise level is recorded here and the frequencies are then investigated for irregularities.

An effective method to obtain early warning about the condition of a bearing in the case of a defect is the BCU measurement (Bearing Control Unit). In the BCU, data is acquired from a sensor positioned close to the bearing. This sensor amplifies the resonance of the impacts that occur due to the damage in the bearing, leading to early discovery of any damage. Possible damage frequencies are assigned to each type of bearing so that the most probably faults - or arising problems - can be rapidly identified.

This method can be used to determine the point in time when the machine should be overhauled.
The more that is known about a possible fault, the more secure the forecast of how long a machine can continue to be operated.