Vestas V47 Controller Retrofit






GNL Service A/S has since their establishment in 2013 focused on delivering an extra service for their customers combined with an ambition towards developing new solutions to improve service and operation of Wind Turbines. With great experience and knowledge in Vestas Turbines, it was a natural choice for GNL Service in 2015 to initiate a collaboration with DEIF A/S towards the development of a retrofit solution for the old Cotas-controllers that we see today in the older Vestas models, such as: Vestas V27, V29, V39 & V42, V44 and the V47 VRCC-series.


One of the challenges with developing a new controller solution in Denmark, is that each wind turbine here requires a rebuilding approval/certificate when vital components are replaced. The controller is here an essential part of the turbine towards securing an optimal operation, but also towards securing that the turbine does not overload.

To fulfill these requirements, DEIF has developed a method to measure the turbines functionality with the original Cotas-controller and their new AWC 500-controller. This method has been running on a test-turbine in Skive, Denmark since 2016. We therefore have some years’ experience of operating the original controller as well as the new AWC 500-controller, to compare with. The method is qualified by Nordic Wind Consultants, who has been involved in the process from the beginning and approved not only the method, but also the measurements and the following documentation for the installation of the solution.

This year DEIF has received the final approval of the retrofit-solution and we can therefore now offer a replacement of the existing controller, where you still keep the original certification of the turbine. As an owner you therefore will be secured similar insurance conditions for the turbine as with a regular replacement. This is ensured through an issued certificate by Nordic Wind Consultants for the re-modelling of the specific turbine. At GNL Service we ensure the entire process for you, from installation to application and certification, without the need for you as an owner to coordinate anything.


What we do in collaboration with DEIF is offer our customers a replacement of the old Cotas-controller with a new AWC 500-controller, with which our experience already shows gives you a better control of your turbine and therefore a better performance, compared to the original controller.

Furthermore, the access to your turbine-data will be optimized, so that we at GNL Service gain direct access to your turbine’s software. This allows us to quickly determine whether if a turbine-stop requires a service-check from us or it is safe to restart the turbine. This ensures you as an owner, a more swift response but also that your turbine producers more energy and therefore more gives you a higher turnover.

The unique part of the new DEIF-solution is, that the Vestas V42, V44 and V47 solutions now are certified to run without the weak V/RCC-system in the turbine. By removing the V/RCC, you will in the future completely avoid further service-expenses related to the V/RCC-system for the rest of the turbine´s lifetime. This combined equals a better economy throughout the entire operation of your turbine. In general, we at GNL Service recommend that you don’t re-invest in a replacement or repair of the VRCC, but instead invest in an upgraded controller that ensures the future operation of your turbine for many years.

If you want to know more about this solution or receive an estimate on how much you can improve your turnover with the new DEIF AWC 500-controller, please reach out to us at: +45 97 59 77 90 or

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Modtag vores business case omkring Vestas V4x retrofit

Ved at udfylde formularen er jeg indforstået med, at jeg tilmelder mig nyhedsbrevet fra GNL Service A/S. Nyhedsbrevet vil være målrettet din virksomhed og sendes ud cirka 4 gange årligt. 



How do you wish to get in touch with us?


Gert Laursen

CEO & Sales

+45 23 26 99 90


Flemming W. Jensen

Technical Planner & Sourcing

+45 22 86 07 07

Jan Laursen

Jan Laursen

Sales & Technical Support

+45 20 83 71 11 


Helle Laursen

Administration & Quality Management

+45 40 86 93 34