Dehn 620151 Earth rod St/tZn 1500mm 20mm type Z

With a triple knurled pin, this coupling offers especially high tensile strength.

Earth rods typically consist of composable single rods with a length of 1.5 m. DEHN earth rods feature a self-locking coupling with bore and pin. The advantage of this construction is that the coupling locks automatically during the driving process, ensuring a mechanically high-strength and electrically safe connection. Additional work steps such as screwing are not necessary.

Different types of impact tools are used to drive in the earth rods. Driving should be carried out at 1200 blows per minute. At a considerably higher blow rate, the power is usually insufficient to reach the required depth with the earth rod. Conversely, at too low a blow frequency, typical of compressed-air driven hammer tools, the blow power may be too high while the blow rate is too low. The weight of the driving hammer should be at least 20 kg.

The possible driving depth of earth electrodes depends on geological conditions. In light soil areas, such as coastal regions or wetlands, depths of 30 m to 40 m can be achieved. In extremely heavy soils, such as sandy soils, the driving depth is often limited to a maximum of 12 m. The more the soil around the earth rod is compressed during installation, the better the electrical contact. An earth rod with a 20 mm outer diameter provides less compression than one with a 25 mm outer diameter. Based on experience, 25 mm outer diameter earth rods yield the best results in heavy soils regarding maximum driving depth and soil compression.