You may have heard that Cat5e and Cat6 cables are tested ? but why? As it turns out, there are numerous reasons testing is an essential part of the industry. Testing is needed for full, true Ethernet connectivity because the underlying system is fairly complex and small issues could lead to poor system functioning.
Testing Cat5e Cables and Cat6 Ethernet Cables
To begin with, cables use copper conductors to transport data signals. In order to ensure the best possible data transmission, the copper conductors need to be tested for efficiency ? to maintain high speeds, they are being used to their full capacity and small issues can lead to large system efficiency losses.
To go back to the issue of complexity: although you may be aware that the cables are comprised of twisted pairs, you may not realize that each pair is twisted to a unique degree in order to ensure best data transmission. When copper conductors are twisted too loose or too tight, the system will likely experience more signal loss and crosstalk issues.
What is Tested
For testing and ensuring a network is using high quality cables that will result in faster systems, there are several testing factors that are used as a standard way to measure quality. Let?s review.
Insertion Loss
Insertion loss is, quite simply, a comparison of signal strength at the beginning of a line and at the end of a line, and is measured in decibels dB. A poorly constructed cable will experience a sizable loss of signal strength by the end of the line. There are several causes behind insertion loss, including energy lost thanks to poor insulation, as well as copper?s potential electrical impedance (also a quality issue). The effect of insertion loss will become more pronounced the longer the line, as more and more signal is lost over distance. Generally speaking, lower quality cables can fare better for short distances since distance emphasizes cable disabilities.
Return loss for cat6 ethernet cables and cat 5e cables is also measured in decibels dB. When a signal is transferred, a percentage of the signal is usually reflected back to the transmitter. The better quality of cable, the lower the amount of signal reflected back. The main cause of high return loss is a poorly terminated wire, frequently at the RJ45 plug. While this will not contribute to lost signals, it does correlate with signal jitter.
Further required tests for cat5 and cat6 ethernet cables include Power Sum NEXT, Near-End Crosstalk, Equal-Level Far-End Crosstalk, DC Loop Resistance, Attenuation-to-Crosstalk ratio, Power Sum ACR, and the Power Sum ELFEXT.
