|Selective plating assumes that the rest of the contact isn't important. |
The popular myth about the cabling business is that it is "commoditized", meaning that you can get cables, connectors, and other components from a variety of manufacturers and only need to worry about price. That is a dangerous myth, however, as in any high tech industry, and is exploited by unscrupulous merchants who promise ultra-low prices in order to win bids. The recent slew of articles regarding counterfeit cabling has shown just how big a threat there is to unsuspecting buyers and technicians. The solution to the problem is to know it exists, so we're going to spell out some of the "secrets" right here.
In reality, cabling is not commoditized, it is standardized, and there is a big difference. Thanks to standards set forth by IEEE, EIA/TIA, UL and others, you can purchase cables made by two different manufacturers and use them in the same application. But that doesn't mean price is the only factor when deciding who to buy from. If you are going to spend any sort of money on a project that requires cabling, you owe it to yourself to check for counterfeit cables before you purchase.
There has been a lot of press recently about the issue of counterfeit cables. Counterfeit cables are cables sold under false pretenses, a growing and disturbing trend. Although most major cable manufacturers have come out with stances against these counterfeits, the economic conditions and the ease of using the Internet to find the cheapest option have created a problem. And any buyer of cabling equipment is at risk if they don't know about this problem. It turns out that there are a lot of ways to cut corners when making cables, which can result in a lower cost and higher margin for the manufacturer, especially if they make a lot of cables over time. But there is a definite price for cutting corners.
|Stripped down, the aluminum center of the conductor is clear. This is CCA, not pure copper.. |
Getting an inferior product is one thing, but consider the costs of having someone troubleshoot network problems, then ripping out the cheap cables you installed, then buying all new cables (hopefully quality ones this time), and finally re-installing them. Also consider the cost of network downtime, of your reputation when you pass on the bad cables in value added projects, and the risk to equipment and even the lives of those around the counterfeit cables. You can see that this is a very serious problem in this industry.
Here are the top seven things you should always look into when you get a low cabling bid:
1. Connector construction. The connectors may be small, but they are a big deal on a cable. In fact, the biggest vulnerability on a cable is at the mating points. Using properly constructed connectors and terminating them properly is critical, but some manufacturers think it is too expensive. For instance, connector contacts are often phosphor bronze coated with nickel for strength and gold for connectivity.
Cutting out the nickel and using just the minimum gold — called "gold flash" or "selective plating" — saves money, but results in an inferior contact that will corrode and fail, especially if there is any stress or if it is mated more than once. Also, the plastic used in the connector should be clear. If it is yellowed or foggy, it may have been made with too much "re-ground" plastic, resulting in a lower burn rating.
2. Cable conductor construction. Using copper-clad-steel (CCS) or copper-clad-aluminum (CCA) saves a lot of money because copper is so expensive. Some industry experts propose that the electrical signal only runs on the surface of a conductor, so the middle of the conductor can be made with a lower-conductive and cheaper material. It's a clever idea, but in practice it doesn't work for most of today's applications. The substituted material will increase attenuation, which can become a bigger and bigger deal as the length between nodes increases. The signal level will drop below the noise and cross-talk levels, resulting in dramatic loss of network speed and, ultimately, downtime. There's a good reason the EIA/TIA has not approved CCS or CCA cable for use in high-speed networks.
3. Cable Jacket Construction. Local and national fire codes are there for a reason. If your application has fire codes as a factor, the jacket material can literally mean the difference between life and death in the case of a fire. If you specify that the cable meets CMP or CMR ratings (per the NEC codes), ask for proof of the jacket material. Counterfeiters often skip the actual tests which ensure jacket compliance because those tests are expensive. But a legitimate business will offer a signed Certificate of Conformance (CoC) for the product they sell, proving this step has been taken.
4. Electrical Performance Testing. The construction of a cable will help it perform, but testing the cable will ensure it. A channel test is a combination of the permanent link and the patch tests to make sure the overall connection works. A common claim by manufacturers is that their products are "Fluke tested", but there are many Fluke tests. If it is a patch cable, then it needs to be "patch" tested. Patch testing a cable is harder to pass and more expensive, but legitimate manufacturers will do it because it ensures the cable conforms to standards and is worth what they are charging. Don't just look at a Fluke test, ask which test the cable passed and ask for results.
5. Cable Markings. It is true that all cables sold in the United States have markings on the jacket to identify where they are from and what standards they conform to, sometimes called a UL "E-file Number" or the manufacturer's name and model number. You can and should look the cable up on UL's database. However, the marking may conform to UL's standard, while the cable does not. A signed CoC will protect against counterfeits, so make sure you get one.
6. Wire Gauges. The wires inside a cable can have a number of gauges, usually measured according to the AWG standard. If you require 24 AWG cable, you should always request a sample cable, cut it open, strip the insulation off of the wires, and measure them. Substituting a smaller gauge is hard to detect, so some manufacturers will do it to save a buck.
7. Don't stop QC after the first sample. While it is a good idea to get a sample before you buy a large amount of cables, some manufacturers will make a so-called "golden sample". They will spare no expense on the sample, making it absolutely perfect to meet your needs just so they can win the bid. Then, when they manufacture the rest of the cables, they will cut any corner they can to pad their margins. Your QC process should be continuous and ongoing, checking every shipment on your dock before you use the cables in any project.
|Uneven and non-existent plating is a hallmark of counterfeit cables. |
There are a couple of ways to protect yourself from the above scenarios. First, always get an advance sample of the cable and always test it. But as we have seen, that's not enough. Whether you buy direct from manufacturers or through authorized distribution channels, always ask for a signed Certificate of Conformance indicating that your vendor has checked and verified the components of the cables you are buying and ensured that they meet the offered specifications. And go beyond even that, putting every shipment through rigorous QC tests to make sure they comply.
Finally, know your vendor. If you are buying from someone for the first time, be suspicious and QC everything. Having a relationship with a vendor is important. A good vendor is there for its customers, a bad vendor is just out for itself. Don't let yourself be burned by counterfeit cables!
Contact: L-com Global Connectivity, 45 Beechwood Drive, North Andover, MA 01845 800-341-5266 or 978-682-6936 fax: 978-689-9484 Web: http://www.L-com.com