For a long time now we have heard that wire can make a difference in audio and video quality, and it is true. But even with this knowledge, most installers have been able to get away with verifying conductivity as a measure of a wires quality, once it is installed.
Times are changing, though. The increasing use of IP networks for control, as well as audio and video distribution, means that a conductivity test is not going to be sufficient anymore. If the systems foundation is fragile or poorly constructed, the system will be poor too. The old adage about building a house on a foundation of sand is still true, and you and your customer will pay the price if you dont validate that your wiring foundation is solid.
The good news is that IP networks are not new; they have been around for decades and a lot is known about the wire (Cat-5, 5e, or 6) as well as how to terminate the wires and test them. Below are a few rules to follow when thinking about wiring:
1. Buy good wire.This is one we often forget. Pulling the cheapest wire may seem like a good financial decision, but overstretch a Cat-5 cable and you will feel the pain in performance. There are many companies out there, and it is a good idea to only install wire from a company that you know and trust.
2. Pull your wire smartly.Pull the cable without over stretching it. And be sure to label your cables, too.
3. Terminate consistently. There are multiple termination options for network cabling (Cat-5, 5e, or 6). Most network-based systems do not care which termination option you use, but if you want to avoid problems, then use the same termination across the entire project.
4. Buy a good termination tool. Poor terminations can be the cause of lots and lots of time spent troubleshooting. A good termination tool is one of those things that you will need in your tool belt.
5. Buy a great tester. This one tool can save days of troubleshooting bad wiring. This is a must have if you are doing anything with IP-based systems and should be capable of doing both a wire map and a BERT test (more on this later). The testers that do active ping tests are also useful if you are going to check whether devices are on the network or not.
6. Run a cable mapping test. This test is a great way to make sure your wires are terminated correctly and to ensure that you did not over stretch a cable. The cable map will tell you how the cable is terminated (568a or b) and will also tell you if you have a break in the wire somewhere. Better yet, most of the good ones will tell you how far down the wire the break is.
7. Run a Bit Error Rate Test (BERT). This test is critical for high-performance systems. While the cable map tells you that your physical wire has conductivity, it does not ensure that you can support the bandwidth needed for your application. For example, if your solution sends uncompressed HD video across the network, the network needs to support gigabit speeds. The BERT test will send varying amounts of data over the wire and verify that your wire is capable of supporting 10, 100, or 1000 Megabits per second of data.
8. Save your wire test results. This is one that many folks forget. In fact, we think its so important at NetStreams that we created a program called the Job Verification Service where installers can save both their wire test results and their configuration files for their NetStreams projects. This helps us, but also helps our dealers by saving them time on the phone and because there is always a place where they can come back and reference previous projects (particularly useful if an employee leaves).
Following these eight simple tips can mean the difference between a great experience and the kind of experience no one likes to talk about. It is also the sign of a professional. Your customers will appreciate the difference.
Sanjay Castelino is vice president of marketing and business at NetStreams, which is based in Austin, Texas.