Tailor-made Jacket

A suitable coat is fancy and protecting, and it also dresses our 100Mbit Ethernet cable in perfect style. Alongside the indisputable advantages in terms of visual impression, a tailor-made jacket also provides a range of technical benefits. In order to avoid that “bare” cable pairs would literally be exposed to the rain, we wrap our 100Mbit cables up in protecting jacketing. Thanks to the interaction of core insulation and jacket material, the cable is better able to deal with the stresses, such as contact with water, which has a very high dielectric constant. If a bare Ethernet cable pair is immersed, the electromagnetic fields that carry the data, spread out in an atypical medium. Water substantially absorbs high frequencies; consequently, the cable will in the end provide only fractions of the high-frequency energy compared with being in a dry state. The data transfer in ‘naked’ cable pairs will respond to even slight wetting. Because of the surface tension, the smallest water drops will merge into one big drop similar to one that might form on a wet plastic box. At this point, the high dielectric constant will create interference in the impedance and thereby generate a reflection of the high-frequency signal. So the incalculable effects caused by several drops will impair a reliable transmission.

Dielectric Material

Electromagnetic radiation is another unpleasant effect. Energy is mostly absorbed in a fully submerged data line pair. But any drops on the conductor will disrupt the cable pair’s symmetry. Part of the energy is transformed into an asymmetric signal and leaves the cable. That way the interference influences other transmission paths. A jacket around the data line pair averts such problems. The functional design of the dielectric’s material properties is also important. The base polymer should attenuate the signal transmission as little as possible and have a stable as well as a low dielectric constant. If a line pair does not have a jacket, its cable polymer must take on that functionality. Additional agents improve reaction to fire and additives enhance good compatibility with other components. But all those materials would make the overall system’s reliability suffer.


As ‘one size fits all’ is not enough, we have prepared our range for all standard applications:

■ The somewhat ‘chunkier’ LEONI Dacar® 546 with its 2 x 0.35mm2 conductors boasts particularly low line attenuation and excellent mechanical performance. This is why it is especially well suited for long transmission paths and, with its 3.8 mm outer diameter, also fits in small installation spaces.

■ LEONI Dacar® 626 and LEONI Dacar® 547 provide especially slim solutions for optimising installation space. Whereas the first, with its 2 x 0.14 mm2 copper conductors, tends to serve placid application scenarios, the other, with its 2 x 0.13mm2 copper alloy and the same outer diameter of 3.2 mm, provides greater tensile strength.

All these cables fulfil such typical specifications as Open Alliance SIG TC2 and SAE J3117. The T3 temperature range, i.e. 125 °C continuous operating temperature, goes without saying when it comes to our 100MBIt Ethernet cables. We also offer other sizes, shielded and unshielded, ‘tailor-made’ for special requirements. The upcoming 1Gbps Ethernet solution is just going through its final validation phase in customer projects. We have launched projects to develop MultiGig Ethernet to provide even more extensive bandwidth