Low-cost level detectors monitor lubricants in wind turbines

Further to the Kyoto conference, renewable energies are developing quickly - including wind power. However, the investment in wind farms is only profitable if the turbines offer significant energy production and a long life expectancy.

One of key concerns is the lubrication of the moving parts, as the significant weight of the rotor generates a critical constraint on the reducer. The correct lubrication of this rotor and the moving parts is vital in order to avoid premature wear of the mechanism. There have to be measures in place, otherwise efficiency and profitability will be compromised.

A vibrating-blades level detector offers a very reliable way to protect the installation against the risks of dry running. Some vibrating detectors come with 40mm short vibrating blades, which allow them to be installed on almost any type of crankcase. Thanks to its millimetre near switching, this type of level detector ensures durable functioning of the wind turbine and does not require any maintenance.

At the heart of the sensor is a piezo drive, which activates the tuning fork to vibrate at its resonant frequency. The frequency of the fork reduces with the immersion, and the frequency change is evaluated by the integrated electronics and converted into a switching signal.

An optimised screwed connection is used to ensure reliability and ruggedness of the piezo drive. With the tuning fork of only 40mm length, this type of sensor works reliably in all liquids, independent of the installation position. Pressure, temperature, foam and bubbles do not influence the switching accuracy. This type of tuning fork also works reliably with changing density and viscosity.

Benefits:

• Very small dimensions
• Very long-term reliability
• Reproducible and process-independent switching point
• Low-cost switch with quick delivery, available to buy online