Cables & wires
Data cable
Data cables – For a fast and trouble-free connection
In today’s world, more and more data is being transferred. However, this data must also increasingly be available quickly. Not only in private, but increasingly also in industry – keyword Industry 4.0, the data transmission rate is rising exponentially. Data cables are extremely important for enabling us to transfer this additional data quickly and smoothly.
What are data cables?
The purpose of a data cable is in the name. They are predominantly used to transfer data. The most important thing is a quick and trouble-free transmission. The most common cables for data transmission are Ethernet cables, also known as patch cables. They are frequently used in Ethernet-based networks. However, they are also used for measurement and control technology, as sensor cables and in control cabinets, industrial plants and residential buildings.
Structure of a data cable
In data cables, the core pairs are generally twisted together (“twisted pair”). This leads to a reduction in faults, as their effects on the cores more or less cancel one another out. The data cables can be protected against irradiation by metal inserts (“shielded/unshielded twisted pair”). In addition to twisted versions, untwisted data lines are also used. They include LiYY (stranded wire with PVC insulation and sheath) and LiYCY cables with additional copper braiding for shielding.
Overview of the data lines and their properties
| Cable type | Sheath / shield | Properties |
| LiYY | PVC / without a shield | Fine-wired copper stranded wires. Core insulation PVC. |
| LiYCY | PVC / shielded | Shield made from tin-plated copper wires. Foil winding. Fine-core copper strands. Core insulation PVC. |
| LiYCY (TP) | PVC / shielded | Shield made from tin-plated copper wires. Foil winding. Fine-core copper strands. Core insulation PVC. Paired cores. With drain wire. |
| LiYCY (TP) UL/ CSA | PVC / shielded | Shield made from tin-plated copper wires. Foil winding. Fine-core copper strands. Core insulation PVC. Paired cores. With drain wire. With UL/CSA approval. |
| UNITRONIC FD CY | PVC / shielded | Cable-track capable. Core insulation PVC. |
| UNITRONIC FD CP plus | PUR / shielded | Cable-track capable. Core insulation PVC. With UL/CSA approval. |
| UNITRONIC FD CP (TP) plus | PUR / shielded | Cable-track capable. Core insulation PVC. With UL/CSA approval. Paired cores. |
Data cables can be based on copper or on fibre optic cables (“glass fibre”). Fibre optic cables allow higher transmission rates. However, because of their lower costs, their easier manufacture and their generally adequate performance, copper cables are much more widespread to date – especially for connection in the field.
In addition to data cables made of stranded wires, there are also data cables with solid cores. They are very suitable for permanent installation in networks where a high degree of manoeuvrability is not required. These cables are also referred to as installation cables.
Overview of the sensor cables
| Cable type | Sheath / shield | Properties |
| LifYY | PVC / without a shield | Core insulation PVC |
| LIFY11Y | PUR / without a shield | Core insulation PVC |
| LIF9Y11Y | PUR / without a shield | Core insulation PP. Cable-track capable. |
| LIF9YC11Y | PUR / shielded | Core insulation PP. Cable chain-compatible. |
Standards for data cables
Network cables with a twisted pair design are assigned to categories (“Cat.”) that describe their performance. The benchmarks for the performance are the operating frequency in MHz and the possible data throughput in Ethernet networks. The older standards Cat 1 to Cat 4 hardly play a role anymore. The following standards are current:
Cat. 5 cables
This standard with a 100 MHz operating frequency includes most network cables that are used today. All current Cat.5 cables allow transmission rates of up to 1 Gbit/s or 1000BASE-T. Therefore, Cat.5 is faster than Fast Ethernet (100BASE-T) by a factor of 10. With Gigabit Ethernet, all four twisted pairs are used, instead of just two as with Fast Ethernet. Accordingly, Gigabit Ethernet uses all eight pins of the RJ45, instead of just four like Fast Ethernet. Cat.5 with copper cables (1000BASE-T) continues to be a good standard for data cables that can meet the prevalent requirements at a reasonable cost.
Cat. 6/6a cables
These cables achieve an operating frequency of 250 or 500 MHz. The difference between Cat.5 and Cat.6 lies in the bandwidth. This means that Cat.6 can perform more data transmissions at the same time. However, a faster transmission is only possible with Cat.6a. This standard is suitable for networks that work at 10 Gbit/s (10GBASE-T).
Cat. 7 cables
In these cables, the operating frequency is 600 to 1000 MHz. This enables these cables to perform more transmissions at 10 Gbit/s (10GBASE-T) than Cat.6a cables.
Cat. 8 cables
These cables allow transmissions at 25, 40 and 100 gigabit per second. Only shielded cables are used here. The possible transmission distances are much shorter than the 100 m that is usual with Ethernet. This category is currently predominantly used for connections within data centres.