Hello, everyone!
Today, I will start to explain UTP cables.
UTP is an abbreviation from Unshielded Twisted Pair. This cable is standardized by EIA/TIA 568 standard or ISO/IEC 11801. This type of copper cable is not expensive and it is very simple to install. Some companies use STP (Shielded Twisted Pair), this cable has shields over each pair in the cable. The second similar cable is ScTP (Screened Twisted Pair). ScTP has a shield around all the pairs. STP and ScTP offer high performance but require more care in installation.
In this article, I will explain UTP cables. UTP cable is composed of four twisted pairs of solid copper wire, insulated to provide good performances – high bandwidth, low attenuation and crosstalk (NEXT, FEXT). In the UTP cable, through each wire of the pair, opposite signals are transmitted. And each wire has half the amplitude of the signal. This is specially designed to emit a little electrical and magnetic field. In the next figure, we can see UTP cable.
Figure 1. UTP cable
The connectors for UTP cables are modular 8 pin connectors or much better known as RJ-45. RJ is an abbreviation from Registered Jack. Figure 2. shows us this connector.
Figure 2. RJ-45
For connecting network devices (PCs, routers, switches, etc), we usually use patch cords with factory-assembled connectors. UTP cables without factory-assembled connectors are also used for connecting network devices, so connectors are installed after installation. In this way, installation is simple and easy.
The maximum length of permanently installed UTP cable for data with patch cords is 100 m. Structured cabling standard defines the maximum length of UTP cable for voice – 800 m. Some categories of UTP cables allow high data rates but at distances shorter than 100 m, for example for Cat 8 the maximum range is 30 m.
There are different categories of UTP cables. They define bandwidth and range. The first category of UTP cable was category 3. Cat 3 was used for 10 Mbps. Today, the minimum speeds in ethernet networks are 100 Mbps. Nowadays, there are UTP cables Cat 5 for fast Ethernet (100 Mbps), Cat 5e (enhanced Cat 5) for 1 Gbps, Cat 6A (augmented Cat 6) for 10 Gbps and Cat 8 for 10-25 Gbps. All of these categories, can see in the next table.
Table 1. Categories of twisted pair cables
I will continue this theme on the next article >> UTP cable (2): UTP termination.
Thank you!
