Limit Switches for Yaw Movement

For yaw movement rotary limit switches play an important role. Mostly they are connected by a pinion gear either to the outer yaw gear belt or to a pinion of one of the yaw motors. In this field they have two main safety-relevant functions:

1. Cable Twist Protection
   The movement of the nacelle is limited to a defined number of rotations to the left and right. By doing this the cables hanging inside the tower are protected against twisting and getting damaged. Mostly beside defining only the total end position a pre-warning-position is also specified with different mechanical contacts.
   
   
2. Position Monitoring
   The integration of electronic components like potentiometers, incremental encoders or absolute encoders allows a very accurate measurement of the nacelle position. The rotary limit switch can be seen as open platform for a big variety of encoders that are defined together with our customers.

All limit switches can be supplied including mixed-up proof calbe plug-connectors and pre-adjusted cams. For easy integration of the limit switches during the time of construction we offer multiple 3D-models for each individual defined specification.

The high protection degree of IP66, the usage of fibreglass-reinforced technopolymer plastic materials with a stainless steel shaft and the use of self-lubricating components guarantee a long-term durability of our rotary limit switches. Already during the design-period of or limit switches all plastic materials, lubrication material and sealing material were selected especially for cold climate conditions as -40°C operational temperature. As unique manufacturer we can offer a total certification of all components for cold climate conditions.

The combination of mechanical switches and electronic position measurement technology enables B-COMMAND rotary limit switches to be used as complete position measurement system. We offer you the long-term experience of the B-COMMAND team in the field of wind power also for a common solution designed for your wind turbine.

Our rotary limit switches offer a big potential of customization. Up to 10 mechanical switches of different types can be mounted inside the housing. For each switch the customer can choose between 10 different types of cams.

The variable shaft length of the stainless steel shaft can be defined freely and also holes, threads or fit-in key solutions are possible. The elongation of the shaft allows the connection of a hollow shaft absolute encoder which is driven directly by the shaft and allowing a maximum accuracy of the position signal of the shaft thus the nacelle.

Also inside the housing of our rotary limit switches a big variety of encoders and other sensors for position monitoring can be mounted. Therefore we offer a high-accuracy 1:1 gear outtake for multiturn encoders. Beside this we are able to mount single turn encoders used on a gear outtake with freely-definable gear ratios.

For the mechanical connection to the yaw gear wheel several pinion gears in different sizes are available. All pinion gears are also self-desinged and manufactured by B-COMMAND. The electrical connection can be done by a cable mixed-up proof plug-connection.