I was talking to a friend of Belden’s at a recent trade show. We were discussing using Category cable for audio, something we have discussed at great length in this blog. “I never use that cable for audio,” said the customer.
“Why not?” I asked.
“Well, all the install Cat 5e or 6 or 6a is solid conductor,” he replied. “And we all know that solid conductors break.”
He was especially insistent that those solid conductors, when soldered into an XLR, often break. This is called ‘work hardening’. Do you believe that? If you do, it probably means that you’ve been using some very cheap cable, because wires that break are not annealed correctly. One of the things you get with good quality cable and good quality manufacturing is annealing. Annealing is a process where the conductor is put into a hot oven to let the molecules come in contact with each other after the drawing process (big wire drawn into smaller wire), but not hot enough to melt the copper. Cheaply made cable sometimes rushes this process or does not anneal at all, creating a brittle wire that will break with just a few flexes. Everyone remembers bell wire from the hardware store. Probably not annealed at all.
Belden’s solid wire, with high-quality annealing, is a different story. I remember when we first came out with MediaTwist (Belden 1872A). This is four pairs of solid wires. At tradeshows, we ran a contest to see if attendees could get the signal running down the cable to stop in one minute. The winner would receive a CD player (or something like that). Attendees became very frustrated because they could not break this cable in one minute no matter how they mangled or flexed the cable. How many flexes was that? Probably a few hundred. I remember some people concentrated on one place on the cable and flexed it as many times as they could. No luck. Some very strong guy finally managed to step on the cable and pull it so hard he broke the cable. The pull strength of this cable is 45 lbs., which means the breaking strength is around 112 lbs. One other person tried to bite it. So we changed future shows to “hands only” (no feet, no teeth).
So how many flexes? When we test for flex-life, we do it in something called a C-track tester, which is the kind of bending you would see in a factory. With this testing equipment, cable will last around 2,000 flexes. In the hands of crazy customers? Hard to say. But if you’re worried about solid conductors breaking, it just depends on how much you paid for the stuff.
Make sure your cables are designed to carry the full signal
Have you ever wondered why some high quality A/V systems deliver such low quality output? The answer is probably in the cables. And it is not that easy to select the right cable, because inferior grade cables can often show a comparable AWG performance in their basic specification, yet deliver very different results. In short, cables unable to withstand high frequencies can result in sound and visual distortion and system incompetence.
On Cable Talk we show that attenuation (the loss of signal) is an important parameter measuring signal strength. Lower attenuation provides a stronger signal which results in a better performing, more robust network. We will show you which cable components are critical and how the frequency being applied to a cable has a direct impact on the strength of the signal. And we will show you how sub-standard cables are simply not up to the job. Read more
Recently we introduced a new industrial Ethernet cable to the market with a techy name, “DataTuff TC Cat 5e Cord Sets for 600V Cable Trays”. While I am not a fan of the name, I am impressed with what this puppy can do. If your application is in heavy industry, or you just want to learn about a very large and very feature-rich Ethernet cord set, I encourage you to read on.
As Ethernet networking gains popularity, it is starting to penetrate more deeply into industrial applications. Manufacturing, power utilities, oil and gas, transportation and other sectors want to attach more types of equipment to their industrial Ethernet infrastructures. This includes power hungry machines such as Motor Control Centers (MCCs), robots, mobile machines, and heavy equipment.
Cabling in these environments can be difficult to install, and it requires extra protection and resilience. Our long-named new cord sets meet these challenges remarkably well. Read more
While I was recently in Amsterdam, the home of IBC, the European version of NAB, someone handed me one of our European competitor’s catalogs. It showed the distance their cables can go at HD and 3G (2K). Funny thing though, they didn’t mention anywhere about the SMPTE formula (-20 dB at half the clock) which is the formula by which we at Belden determine the recommended distance of our cables. In fact, we can generate these numbers before we even make the cable. These are “safe distances” and are about half way to the digital cliff. I say “about” because, as chips improve, the effective distance keeps getting longer and longer. It is a common complaint we get, that you can go twice (even close to three times) the distances we show. Yes, those “recommended” distances are intended to keep you safe. Slap on connectors with the same bandwidth and return loss and you’re good to go.
We constantly hear stories about other manufacturers saying they go “much farther than the Belden cable”. Are those numbers based on the SMPTE formula? If not, then they better be at least twice as far as our numbers. Then there are those manufacturers who simply add 2 meters (meters in Europe) to each of the numbers in our chart that just proves they didn’t know where those numbers came from.
And then there is Return Loss testing, talking about how perfect the cable is by tracking its impedance beyond the clock. For 3G (which I am going to start calling 2K), this required us to test out to 4.5 GHz and that cost us a pile of money. An ex-employee of one of our competitors told us that when Belden went to 4.5 GHz the company he was working for just changed the number on their jacket printing to 5 GHz. We have a technical term for this kind of measurement, but I can’t publish it in this blog ☺. Now you could take a regular network analyzer and put 5 GHz (or any frequency) on a cable. Then it would be true that the cable was tested at 5 GHz. But the real question is, what did these tests show? What were the results of this testing?
As the customer or integrator or purchaser, this is your job, to ask for that test data. You can take your Yugo on the racetrack. It will go round and round. But you win a race? Not very likely! I often tell people that my company car will go 300 miles an hour…..over a cliff.
My Belden friends in Europe got samples of these competitors’ cables to test them and take them apart. This is the same example I used in last week’s blog where things as simple as the braid were way off from the Belden spec. Our cable has a 95% braid over 100% foil. The braid portion of one competitor ranged from 43% to 84%, never even close to 95%. No wonder their cable is half the price of the Belden equivalent. And yet, they put the spec sheet in front of the customer with numbers bigger, farther, better than Belden, and they do get sales. Like almost every cable, if they’re short enough, anything works.
So I’ll get to the point of this post, which is to restate what you already know: the folks I work with at Belden know their stuff and do the hard work each time we put out a cable. We test, test and then test. We give you the numbers on our spec sheets that are important to you. We deliver a product you can rely on every time. Just like we say in one of our marketing slogans: Be Certain. Belden.
I can’t wait until they bring out 4K single-link video cable! Maybe again they’ll just change the number printed on their cable?
If you work with any kind of cable, certainly audio and video cables, then you are familiar with the shields in these constructions. Some are braid shields, good at low frequencies, starting at 1 kHz and slowly deteriorating around 400 MHz. (The openings in the braid structure begin to look bigger and bigger at shorter wavelengths.) Then we have foil shields. These are superior at high frequencies, starting around 10 MHz and going as far up as we can go. (Up to 20 GHz in some designs.) The foil is too thin and fragile to use it as a connection point, so, if you only have a foil shield, we give you a drain wire, a bare wire touching the foil that is your connection point. The ideal shield is a combination of foil plus braid. And the best of those is the highest braid coverage (around 95%) with a foil underneath.
You can even improve on that. A tri-shield, with an outer and inner foil, and a 95% braid in-between, is even better shield effectiveness. We have extended our well-known precision digital video cables with a new product line (DNH Series) that exactly addresses this need. It is available in different colors and in all sizes ranging from Mini RG59, RG59 to RG6 and RG11. Quad shields (foil/braid/foil/braid) would probably be even better, but I don’t think it has even been tried with two copper 95% braid shields. It would require special connectors since the cable would be much bigger. If you know quad shielding, it’s probably in the broadband/CATV world, where the two braids are 40% and 60% coverage, and are made with aluminum wires. This low braid coverage makes a huge difference in shield effectiveness.
In fact, we recently tested one of our off-shore competitors who claimed to make identical cables to our precision digital video cables, like 1694A. Testing dozens of reels bought on the open market, not a single one got close to the 95% shield we make. Their closest was 84% and their worst was below 50%. I was talking to one of our engineers at the IBC show in Holland. “All you have to do is weigh the reel,” he told me. We all use the same plastics and same wire (pretty much), so if the reel is 20% or 30% less weight than the Belden stuff, well, that difference has to come from somewhere!
We know that customers are always looking for cost reduction and therefore we recently launched at IBC a new market performance video cable range (70000 Series) which meets the industry standards perfectly and is our best price/performance product. Together with the DNH Series the new 70000 Series is also designed to fit seamlessly with our 1-Piece HD BNC compression connectors. This combination will save more money, as it reduces installation time and labor cost!
If you have a foil and braid, you don’t need a drain wire. The braid is also the connection point for the foil. If you put on a BNC, you would make contact with both foil and braid, although the braid is the main mechanical connection. However, we do make one cable that has a braid shield and a drain wire. That is our top-of-the-line microphone cable, Belden 1800F. It has a flexible tinned copper French Braid shield, with a bare copper drain wire underneath. The drain wire makes it very easy to connectorize this cable. And it’s a different color (copper) from the shield above (silver-colored tin). You don’t have to separate and un-comb the braid. Just cut it off and use the drain wire. Simple! Here’s a picture of that construction.
It’s not long to go now before the world of industrial automation comes together in Nuremburg for the annual SPS/IPC/Drives show. And it’s not difficult for us at Belden to get excited, because once again we will be able to offer more and more effective solutions than ever before. Read more
Discussions surrounding whether or not to test a fiber channel with the patch cords have been unclear. The answer to this long-standing question is “it depends.” Let’s take a closer a look.
First Check the Spec
In reality, the main deciding factor for whether to test the channel with the patch cords included or to just test the permanent link depends on the specification provided by the end user or their consultant. If the spec calls for it, you need to include them. It’s that simple.
Then Consider the Facts
If after checking the spec the question still remains as to whether or not patch cords should be included in channel testing, consider the fact that patch cords are factory terminated and offer a lower risk of defect and errors. Installation of the permanent link typically has much more impact on the performance and insertion loss of the channel.
Sometimes it is also not logistically feasible to test the channel with the patch cords because they are often not in place during initial testing, before active equipment is installed and up and running. They are also regularly moved or changed during reconfigurations without necessarily re-testing the channel.
Know What Can Go Wrong
While most should not have to worry about testing the channel with the patch cords (unless it’s specified), the fact remains that sometimes things can go wrong. Fiber patch cords can have dirty end faces or they could be damaged—especially since they are a moveable component.
With many of today’s data centers now consisting of flattened architectures that deploy end of row (EoR) and middle of row (MoR) designs where 10GBASE-T access switches connect to servers within the row, horizontal cabling lengths have become shorter than ever.
The channel length between an access switch and a server in a neighboring cabinet can be as short as three meters for a two-connector channel. Since it is actually more difficult to meet category 6A performance parameters for 10GBASE-T over a shorter distance, it’s important to make sure that your cabling solutions are up to par. If not, you might find yourself having to deal with excess cabling slack and potential airflow concerns.
Not All Pre-terms are Equal
For popular EoR and MoR modular designs that use standardized configurations for server cabinets and enable a predictable “pay as you grow” methodology, many data center managers are finding that pre-terminated copper solutions are ideal for the fixed portion of the channel—from the patch panels at the access switch to the patch panels in the server cabinets. They require less skill and labor to deploy, allowing installations and upgrades in a fraction of the time required for field terminations.
Since the main reason for pre-terminated copper cabling is to speed deployment, it only makes sense to look for solutions that offer the fastest and easiest installation. Intuitiveness of the plug-and-play method, ease of routing and cable management all impact deployment speed.
In last week’s Practical SCADA Security blog, I discussed how the discovered in SCADA masters are carving big holes in the NERC’s concept of the Electronic Security Perimeter (ESP). Dale Peterson started the ball rolling in his blog ““. Then Darren Highfill posted a explaining that the vulnerabilities don’t even require the attacker climb a fence.
DNP3 serial links connect millions of physically insecure pad and pole-mounted devices. Accessing just one of those devices opens the door to a system wide attack. Since there is no way that every one of these devices can be inside the perimeter, the concept of NERC’s ESP is fatally flawed.
Is this a potential backdoor into the power grid?