By: Mr. Shajan George, Technical Director at R&M India
It is hard to believe just how much patch cords have to take. They suffer daily from mechanical stress due to handling and unwanted mishaps. In many applications, patch cords are also exposed to harsh environmental conditions such as heat, dust, sunlight and humidity. And when you add Power over Ethernet (PoE) to the mix, cables and connectors are exposed to thermal stress because of the current flow. Patch cords age quickly, but they should still guarantee absolutely interference-free transmission. At the same time they should be as thin and flexible as possible in order to achieve a high packing density and good handling.
“Patch cords are not just any piece of cable with two RJ45 plugs. They are actually the most exposed components of LAN cabling. And as is the case with a chain, the whole is only as strong as the weakest link in a LAN. They are the tangible link between an IT device and the LAN. The more high-capability terminal equipment there is in the network, the more important the patch cords become. However, each use case scenario has different requirements. A whole range of different criteria has to be taken into consideration to ensure the right patch cord is chosen,” said Shajan George, Technical Director at R&M India.
First of all there is the question of the use case scenario and environmental conditions. The more demanding the transmission, the more powerful the patch cord should be. Sources of interference from the surroundings influence the choice of cable construction. The question as to whether PoE is to be used on a broad basis is becoming increasingly important. When this is the case, the only patch cords that should be used are those which can transfer the amount to be transmitted for the entire service life (powerSafe).
Criteria for selecting copper patch cords
- Planned transmission performance of 1 or 2.5 or 5 or 10 or 40 Gbit/s – Category: Cat. 6 or Cat. 6A or Cat.8
- High-performance or continuous PoE: powerSafe or future safe for 4PPoE
- EMC environment: cable construction, shielding: S/FTP, U/FTP or unshielded (U/UTP)
- Handling: diameter, wire cross-section, bending radius, cable flexibility
- Sensitivity of the application, required capability: wiring technology, tension relief, connector construction
- Fire behavior: plastic cable jacket
- User convenience and error avoidances: color coding, security systems
- Availability, logistics
- Price/performance ratio
The universal and flexible patch cord R&Mfreenet is the appropriate product for the various areas of use. R&Mfreenet cables demonstrate the very best quality, sustainable system margins and application-oriented features. The optional security system enables consistent color coding and plug-in/plug-out protection to avoid errors in operation without additional logistical costs. The conductors in the connectors are wired exclusively using insulation displacement technology, IDC, in other words, powerSafe wiring. For areas of application which do not require the added value of the R&Mfreenet patch cord, R&M offers the new patch cord family R&Mclassic in select markets. The concept of this patch cord family is based on IPC (insulation piercing contact) and has an attractive price/performance ratio.
With IDC, the conductor is fixed between the contact halves of a spring contact. The contact halves cut through the insulation, press resiliently on the stranded wire and thus establish the contact. The contact resistance and transmission properties of an IDC connection remain permanently low and stable. IDC is the optimal basis for using Power over Ethernet with high currents in continuous operation. R&M is one of the pioneers of IDC technology for RJ45 patch cords. R&Mfreenet cables are exclusively equipped with IDC wiring. In the case of IPC, a metal tip pierces the core insulation and makes the connection to the stranded wire. This method is state of the art and economical, but does have certain disadvantages. The contact resistance becomes uncontrollably worse over time due to aging and environmental influences. Piercing technology cables are therefore not recommended for Power over Ethernet transmission over long periods of time and at higher power levels.