Customer reference Windunie: Vibration monitoring & analysis

Vibration monitoring and analysis on wind turbines in the Netherlands

Windunie is a collaboration between owners of wind turbines throughout the Netherlands. The warranty of some of the wind turbines at one of their wind parks was expiring at the end of 2022. Windunie has engaged Istec as brand-independent vibration specialist to monitor the condition of the turbines.

When the warranty of a wind turbine is about to expire, a final inspection is conducted by the manufacturer (OEM) of the turbine to assess their mechanical condition. During this inspection multiple parameters are measured and analyzed to determine the condition of the wind turbines.

To ensure additional insight into the mechanical condition of the wind turbine drive train and the effectiveness of the condition monitoring program, Windunie has contacted Istec, as independent third party, to conduct vibration analyses on two Vestas wind turbines.


Wind turbines are complex machines due to their multitude of vibration measurement points, a slow-turning main shaft, a gearbox with multiple stages, and a fast rotating generator (1500 RPM).

While Istec offers vibration measurement hardware, we are able to provide our vibration monitoring services brand-independently. In this case a Brüel & Kjær Vibro vibration measurement system and 12 accelerometers were already present. Thus, the existing measurement set-up was used to retrieve vibration data.


Istec had to create a baseline for the condition of the turbines, which is used to compare to future data analyses. Remote data was accessible to istec, and our experts were able to view and analyze the data remotely via cloud access. Within a week, the data was collected and analyzed, and a baseline was created.

During this project Istec created the foundation to perform periodic analyses every quarter by collecting data remotely, analyzing it and comparing it with the baseline. By doing so, any deviations in the data will be detected fast and developing damages can be dealt with accordingly.


  • The data was collected, analyzed, and conclusions/recommendations were made within a week
  • Short communication lines, allowing for quick responses, and high availability of Istec specialists
  • Istec utilized the four-eyes principle for the verification of the data analysis and the conclusions drawn from it


Windunie can rely on the independent advice of the vibration specialists from Istec. Through the early detection of developing damages, it is now possible to perform predictive maintenance. Thanks to the ability to remotely access vibration data, Istec can quickly and adequately respond when necessary. This enables maintenance to be efficiently planned and executed, contributing to optimal operation of Windunie’s wind turbines.