15 Mar Testing a Network Data Cabling Installation
Having a set of testing procedures for a newly installed network cabling system is an essential part of the installation process as they can not only ensure every component is connected and working properly and efficiently, but also help to troubleshoot any problems that may arise at a later date.
We know that when planning a network cabling installation we need to choose the correct cabling and components for the applications that the system will be supporting, along with taking into account any environmental factors present and all the data cabling standards that apply. Incorporating a set of testing procedures as well will enable you to check a number of important aspects, which should result in eliminating any possible connection or performance problems.
Testing procedures should include things like checking that each of the individual cables are free of any defects and have been routed correctly around light fixtures or electrical equipment. Making sure that all the cable connectors has been attached properly and the wires have been connected at both ends to the correct pins. These testing procedures also ensure that all the cables and different components that the system consists of conform to the required EIA & TIA standards and specifications.
Even if you are not actually installing the network cabling system yourself, but have instead wisely chosen to get a professional network cabling company to do the job for you; it is a good idea to familiarise yourself with the type of tests that the installers perform along with the results that they produce.
The majority of copper cabling that is used in network cabling installations today is one of the types of twisted-pair cable. Due to the number of individual wire connections that are involved and the different standards that apply, the testing procedures are more complicated for twisted pair than for any other type of cable. The three basic tests that should always be carried out in accordance with the EIA/TIA-568 specifications though for all twisted pair cables are wire mapping, cable length and high speed performance.
With twisted-pair cabling you need to test each cable making sure that all the individual wires are connected properly and wire mapping is one of the simplest yet most important tests to do. A wire map testing device transmits a signal through each of the individual wires in the cable to check if there are any faults in the connections.
The tester can identify a number of the defects with the conductors within the pair of the cable, such as broken or unconnected wires along with different types of shorts; which happen when pins or wires that are connected properly to each other. The majority of faults found are generally caused by incorrect installations, though some can be due to having either damaged or faulty components.
Testing Cable Length
All the cables that you lay within a network cabling system should already be limited to the maximum lengths that are laid out in the standards specifications. However you should still user a tester to check the electrical length of the twisted pair wires within the cables, as these are twisted together they will be physically longer than the actual length of the cable. Another reason why you check the cable length is to test for any shorts, opens or breaks in connections.
You can test the cable length by using a specially calibrated capacitive tester, but a better option is to do it with a Time Domain Reflector tester as this can also measure the distance to any faults that may show up.
The above testing procedures test the physical properties of the network cabling system to make sure that everything is connected and works properly and it is also vital that you check the transmission performance of your newly installed network. This will make sure that the signal is both strong and fast enough to meet the networks performance requirements. These tests require a more sophisticated bit of kit than the testers used for basic wire mapping as they include checking the following aspects:
Attenuation – Measuring any reduction in the strength of the signal
Cross-talk – Evaluating the cables ability to reject any electromagnetic interference
Propagation Delay – Gauging the amount of time a signal is delayed when travelling through a wire
Delay Skew – See the difference in propagation delay between any 2 twisted pairs in the same cable
There are a wide variety of different makes and types of network cable testers available on the market today. At Bridge Cable one piece of tech that we regularly use is a Certifier Tester and this can perform a wide variety of tests – below is a short training video on how to use this network cable tester.