On average, a single bolt of lightning generates temperatures in excess of 20,000 degrees Celsius, several times hotter than the surface of the sun. And given that wind turbines are tall structures out in the open, you can be sure to get hit sooner or later. What you can be less sure of is what happened to your turbine when lightning struck.
On average, a single bolt of lightning generates temperatures in excess of 20,000 degrees Celsius, several times hotter than the surface of the sun. And given that wind turbines are tall structures out in the open, you can be sure to get hit sooner or later. What you can be less sure of is what happened to your turbine when lightning struck.
The economical way to get information about the lightning that hits your turbine is a lightning card from Polytech. A card with a magnetic strip on it (exactly like a credit card, also the same size) is placed in the blade root on the lighting protection cable. When lightning hits the turbine, the current flows through the cable to the ground, and as it passes through the cable, a magnetic field is induced, thereby damaging the information on the magnetic strip of the lightning card. Polytech’s card reader and special software then lets you translate the damage on the card to the current of the lighting.
This simple yet solid solution has made Polytech’s lightning card the preferred choice for thousands of turbines across the globe. It is available for retrofit on your turbine.
The lightning card measures the lightning current in the conductor by registering the size of the magnetic field caused by the current.
The measurement is a purely magnetic registration and the process is irreversible, which means that the registration saved can only be overwritten by a lightning strike with more current.
The card can be replaced and read either during routine replacement or if a lightning strike is suspected.
Benefits:
The card holder is fitted to the conductor using plastic strips to keep the lightning card firmly in place in a precisely defined position.
The card holder is not affected by the lightning current.
The lightning card reader is a separate unit used to convert the measurement taken by the card into a reading expressed in kiloamperes.
The card reader and the software supplied with it can be used to save the reading in a database. From here, the system can be used to generate reports (PDF) as documentation of the measurement.
The card reader requires a 12 V power supply and can therefore be powered from a service vehicle or, using the transformer supplied, via a mains connection.
The card reader can be used to read corresponding cards of other makes.
Click here to download the LCS software.
