Are your connectors time bombs?Master punching down 110 blocks through careful inspections.
Over the years in my work as a consultant involved with the physical layer (the copper and glass glue that holds this whole hi-tech world together) I have run into one problem over and over: IDC punch-down failures. Perhaps I can save others some frustration.
I have never been short of frustration.
My first trip to Great Britain Great Britain, officially United Kingdom of Great Britain and Northern Ireland, constitutional monarchy (2005 est. pop. 60,441,000), 94,226 sq mi (244,044 sq km), on the British Isles, off W Europe. The country is often referred to simply as Britain. was on behalf of a large Canadian corporation. I was supposed to look over the CAT 5 cable installation in one of its plants. Head office sent a letter of introduction in advance of my trip. The letter said I "was being sent to audit the facility and should be given full cooperation and had camera-on-site privileges." When I arrived, it was like walking into a deep freeze deep freeze
see freezer. . It took me three days of buying lunches and holding private meetings before they realized that I was sent there by the home office to help, not be the corporate hatchet hatchet: see tomahawk. man.
I really did want to help.
A microscopic look at the metal contact forks on 110 IDC punch-down blocks yields three common types of geometry. Figure 1A shows sharp right-angle corners at the wire entry point. The corners may even have sharp burrs from the stamping/punching process during manufacture. Figure 1B shows a bevelled bev·el
1. The angle or inclination of a line or surface that meets another at any angle but 90°.
2. Two rules joined together as adjustable arms used to measure or draw angles of any size or to fix a surface at an angle. entry design. Figure 1C shows a rounded wire-entry design.
[Figure 1 ILLUSTRATION OMITTED]
If we now try to punch down a conductor into these IDC forks, we get varying success rates. The forks of Figures 1B and 1C displace insulation and guide the conductor into the contact grooves. Forks from the Figure 1A group pose a problem. Study Figure 3 and note how the sharp edges of the forks "jam" into the copper-conductor cross section.
[Figures 2-3 ILLUSTRATION OMITTED]
There are three possible outcomes of an IDC punch down into a Figure 1A cross-section fork. You can get a good contact as in Figure 2A. Figures 2B and 2C punch downs represent big-time problems. Often, they pass installer visual inspection and--even worse usually make contact so that they pass certification testing. The mode for this connection relies on the retention force of the plastic slots of the wire block against the plastic insulation of the wire on both sides. Both of these connections are ticking time bombs.
The normal IDC punch-down cycle starts with the conductor being located above the slots of the metal fork and being held lightly by the plastic slots of the punch-down block. The punch-down tool then forces the conductor into the slot of the metal fork, and, during that process, it displaces the insulation to make a gas-tight metal-to-metal contact.
Look at the fork with the slot geometry of Figure 1A. When you try to punch down a conductor, the IDC cycle starts with the sharp corners of the forks digging into the copper conductor. At this point, the conductor either breaks and you get a punch down as in Figure 2B, or the conductor jams tightly enough in the slot of the punch-down tool to give you a termination that looks like Figure 2C. A Figure 2C termination can be spotted by careful visual inspection. Unfortunately, the Figure 2B termination looks fine and often passes testing.
This termination can drive you nuts.
After running into a number of Figure 2C terminations in one day, I spent the next day in the lab with a stereo microscope. I had a fairly broad range of products at my disposal to examine. To my surprise, I found a wide variation in the wire lead-in corners of the IDC forks. Some forks actually had sharp edges with protruding pro·trude
v. pro·trud·ed, pro·trud·ing, pro·trudes
To push or thrust outward.
To jut out; project. See Synonyms at bulge. burrs. I was also surprised to see that this was more of a quality-control issue than being attributable to one specific manufacturer.
An internal quality-control program that involves testing and inspection of incoming product can yield a large payback Payback
The length of time it takes to recover the initial cost of a project, without regard to the time value of money. . Both spot checks and production lot tracking and testing can pay off. Installer training and supervision is also important. Spending time "Spending Time" is the first single released by Christian artist Stellar Kart.
The lyrics describe the band members desire to spend "more time with God". "Sometimes it’s a real struggle to spend time with God. with the install crew allows you to spot any problems as they develop. Installers are very vocal about things they don't like. Careful visual inspection at every step is also essential and can spot problems that testing can miss.
I have great respect for installers and always end up getting an earful ear·ful
1. An abundant or excessive amount of something heard, such as talk or music.
2. Gossip, especially of an intimate or scandalous nature.
3. A scolding or reprimand. .
Network stability starts at the physical layer, yet many managers target this area for cost reduction or simply ignore it. Certification of the cable plant is a complex issue. Often, managers don't know Don't know (DK, DKed)
"Don't know the trade." A Street expression used whenever one party lacks knowledge of a trade or receives conflicting instructions from the other party. what they should expect. I have seen companies pass off tests using LED-continuity testers as CAT 5 cable certification ! However, doing tests with a sophisticated cable tester A cable tester is an electronic device used to verify the electrical connections in a cable or other wired assembly. Generally a cable tester consists of:
Product selection, workmanship, thorough visual inspections, and full testing all are required inputs to the "AND gate" of the certification process. You can throw a lighted firecracker into a bear cave and, as long as the fuse is burning, nothing will happen. However, when the firecracker goes off, you will be facing an angry bear looking for Looking for
In the context of general equities, this describing a buy interest in which a dealer is asked to offer stock, often involving a capital commitment. Antithesis of in touch with. a fight.
Networks ate much the same.
Rygalo has been involved over the last 15 years as a consultant in the design and troubleshooting of R.F. communications systems In telecommunication, a communications system is a collection of individual communications networks, transmission systems, relay stations, tributary stations, and data terminal equipment (DTE) usually capable of interconnection and interoperation to form an integrated whole. , network TIA/EIA and BICSI (Building Industry Consulting Service International, Tampa, FL, www.bicsi.org) An international telecommunications association providing education, registration and resources for professionals involved in the design and installation of low-voltage distribution systems in commercial and physical layer, power quality, and grounding EMI (ElectroMagnetic Interference) An electrical disturbance in a system due to natural phenomena, low-frequency waves from electromechanical devices or high-frequency waves (RFI) from chips and other electronic devices. Allowable limits are governed by the FCC. . He can be reached at 780-453-1008.