A Brief Look at Ethernet Cable Construction

There are a lot of variations of Ethernet cable out there: shielded, unshielded, 4 pair, 25 pair, etc. At its' most basic, Ethernet cable consists of 4 twisted pairs covered in an outer sheath. Some cables may include a spline or star filler to help keep the cable round. Other options include rip cords (for stripping the sheath) and drain wires. Available in both stranded and solid conductor forms, permanent wiring (the wiring inside the wall that connects a wall socket to a central patch panel) is solid core, while patch cables are typically stranded. Although it’s fairly durable, never bend the cable tighter than four times the outside diameter of the cable – the cable will develop hotspots and performance will degrade.

CX4 Cables

Most network cables are insulated with polyethylene or PVC, which are both halogen-based. In a fire, halogen-containing plastics release hydrogen chloride, a poisonous gas that forms hydrochloric acid when it comes in contact with water. Halogen-free cables, sometimes called low smoke zero halogen (LSZH or LSOH), do not produce a dangerous gas/acid combination or toxic smoke when exposed to flame. Low smoke zero halogen sheathing is becoming popular and, in some cases, a system requirement. Other benefits of halogen-free cable include:

• Weight: LSOH is often lighter, so overall cable network weight can be reduced
• Environmental Impact: The fewer toxic chemicals used in construction mean less impact downstream

Some cables are “UV-rated” or “UV-stable” meaning they can be exposed to outdoor UV radiation without significant destruction/degradation. Non-UV stable jackets, when subjected to direct sunlight and other substances, will leach out its plasticizers, often making the cable jacket feel slightly greasy.

Pin Position of a Ethernet Cable

10BASE-T and 100BASE-TX only require two pairs to operate, located on pins 1 plus 2 and pins 3 plus 6. Since 10BASE-T and 100BASE-TX need only two pairs and Cat 5/5e cable has four pairs, it is possible (but not standards compliant) to use the unused pairs (pins 4–5, 7–8) for PoE. However, 1000BASE-T requires all four pairs to operate.

Sopto supplies high quality copper cables, like SFP+ Twinax Cables, XFP to XFP Cables and so on with reasonable price for cloud storage data centers applications. For the newest quotes, please contact a Sopto representative by calling 86-755-36946668, or by sending an email to info@sopto.com. For more info, please browse our website.