Typical LAN Structured Cabling: The Basics

January 16, 2014 at 10:00 AM

Keeping it neat

Typical LAN Structured Cabling Setup

We know things can get messy in your commercial building when installing any sort of cabling system. Many cabling systems require a full wiring closet or server room including racks, panels, patch cords, lightning protectors, routers, switches, and media converters. All of which is supported by a staff of IT professionals. 


Phew. That’s a lot to manage. And having Internet access in a commercial building is no longer just an option. It is a must.


Even if you are doing most of your file sharing and other network activities in the cloud, you can't get by without the basic cabling linking your office to an ISP. 


So what’s the solution? A Structured Cabling System, which is the cabling, connectors and accessories that make up the Local Area Network (LAN) inside a building.  At a minimum, this consists of a modem, router/network switch and Ethernet cabling. 



Here's the trick

Often you need something more complex than just a computer connected to the Internet.  That means you'll need an Ethernet router to handle internal network addressing, securing resources and providing a connection to the Wide Area Network (WAN).  You will also most likely require Ethernet switches to distribute traffic to many computers and servers in your LAN. 

Typical Ethernet Cable with RJ45 ConnectorSince routers and switches can't work alone, you will require Ethernet cabling- possibly a lot of it.  And when you have a lot of cabling, things can get even messier. Try out these high-quality right-angle Ethernet patch cables along with cable management rack panels to keep your area neat and organized. 


With all the different cables going to different systems, its obvious things can get confusing. We suggest color coding your network too. Check out our wide range of colors for Ethernet cables, here. If you specify that a certain color cable carries a certain signal type (such as phone or network traffic), you ensure that everyone who works on your network wiring can visually identify critical connections before they are disconnected.


As your network grows, you also need your structured cabling system to be scalable.  One good way to do this is to employ a well organized rack layout and utilize good cable management practices. This will make future growth easier to manage within your server room. Plan for future expansion by also including blank filler panels between patching sections in a rack and between network switching/routing equipment.


Around the building, set up plenty of user access points by terminating a minimum of two network ports per office workspace.  Installing keystone jacks in aesthetically pleasing wall plates or surface mount boxes will give an office space a finished look.

Typical Enclosure Setup with power, lightning protection, and networking productsFor remote and secure locations, use enclosures to house both wired and wireless equipment. To power these products, install Power over Ethernet (PoE) injectors and splitters that will eliminate the need for complicated electrical re-wiring. If the location is too far for traditional Ethernet wiring (about 100 meters and further), consider setting up a fiber optic link using commercial or industrial grade media converters

Finally, never forget the importance of lightning protection.  Electrical surges can occur anywhere with devastating effects on expensive and critical equipment. Nearly anything that carries an electrical current is vulnerable. 


Need more tips? Click here for our Telecom/Modular (Premise Wiring) tutorial page. 


Tips on Selecting an Ethernet Media Converter

January 9, 2014 at 10:00 AM

L-com Industrial Ethernet Media Converter (DIN Rail mounting)

Fiber optic technology is taking the Ethernet networking world by storm. It is faster, completely resistant to EMI/RFI, and offers incredible distances between nodes.


But fiber is not quite ready for all LAN applications. In many cases it makes sense to keep a copper network intact and lay a fiber network over it. So, here we find a need in our industry for a device that will convert seamlessly between the fiber optic network and the copper network without loss of speed.


We call these devices Ethernet media converters.



Industrial vs. Commercial


Commercial Media Converters

The first consideration in finding the proper converter for your application is whether your Ethernet media converter will be installed in a commercial or industrial environment. A commercial environment would include a typical office or clean room, and an industrial environment includes places with dust, moisture, temperature variations, vibrations, and other complications.


We've gone over the differences between the two in regards to switches before, but the same rules apply for media converters. It is very important not to confuse industrial versus commercial converters. While an industrial Ethernet media converter can operate in a commercial environment, it costs more and generally supports features not commonly found in a commercial environment such as DC power. On the other hand, a commercial Ethernet media converter should not be used in an industrial environment as network downtime and system failure can occur.


Single mode vs. Multimode


Fiber Glass Types

There are two main "modes" for fiber optic cabling: single mode and multimode. L-com has a great tutorial and video with in-depth explanation. In general, a single mode system is more expensive, but also provides better signal strength over large distances (up to 100km or more).


Multimode is much more affordable and can be used in distances of up to 2km, depending on network speed and bandwidth. Again, don't confuse the two! If you are running multimode cable, you need a multimode Ethernet media converter; a single mode version will not work.


Fiber Optic Connector Types



Fiber optic cables have their own unique connector types. There's a good video explaining fiber connectors here. Unlike copper, fiber connectors are very difficult to install properly in the field, and there aren't many options for converting a connector type with a passive adapter (although L-com does carry ST-SC, ST-FC and LC-SC adapters, among others, on its fiber optic adapters page). It is best to match the connector type with the device so they can be easily connected and no extra loss is incurred.


Remember, L-com stocks hundreds of factory terminated fiber optic cables off-the-shelf. We can custom manufacture fiber cables without minimum order quantities and with very short lead times, so you don't need to re-terminate or adapt a mismatched cable.



Other Features


Before ordering your media converter, also consider things like mounting method (DIN rails, 19" racks or chassis, or just placed on a shelf), network speed (10/100/1000 Mbps), and how you will get power to the unit. A properly installed media converter can both future-proof and provide redundancy for your network for years to come!


Quick note: Installing Ethernet media converters may require other components as well, such as fiber optic cables, Ethernet cables, and racks and accessories.

Hot Stuff! Low Smoke Zero Halogen (LSZH) USB Cables

December 3, 2013 at 10:00 AM

Flammability and Toxicity Ratings on Different Cable Types





What would happen if your cables caught on fire?


There's actually much more to consider than the obvious flames and danger. Gasses you can't see and destruction to the inner cable conductors can endanger lives and destroy valuable communications equipment. 


To avoid that unknown, here’s a snapshot of USB cable jackets and looking into what yours is made of. Most commercially available cable assemblies have an outer jacket made from polyvinyl chloride, or PVC for short. Another alternative chemical compound that a cable's outer jacket can be made of is called Low Smoke Zero Halogen (LSZH), which reduces the amount of toxic and corrosive gases emitted during combustion.   


PVC is a durable, flexible plastic material perfect for most general applications.  If you were to buy a deluxe or premium USB cable, PVC is the type of jacket it would have. Yet for all of its benefits, PVC has some downsides- the biggest of which is the way it burns


Once PVC has caught fire it typically burns freely for a long while and releases toxic gasses in the process, including harmful halogens. In a building fire, the danger is that flames can burn along the cable jackets behind a wall and leap from room to room or floor to floor.   In most building fires the toxic gasses are not a big factor since occupants can get outside, and since USB cable is rarely run behind a wall, most manufacturers don't bother making them with non-PVC jackets.


But in some instances, a building fire isn’t the only scenario to consider.  Military and aerospace applications add another element to the danger:  people don’t always have outdoor access.  In fact, any application where people are working in close proximity with cable assemblies and cannot easily get ventilation in the event of a fire would require a special jacket material for the cables.


USB with LSZH Jackets


Though USB is not often run behind a wall and the USB standard is typically only used in peripheral-to-computer applications (including many in military and aerospace environments), having many PVC USB cables can lead to a dangerous situation.  LSZH cables, on the other hand, are self extinguishing. For that reason, L-com has made LSZH USB cables an off-the-shelf product, available for same-day shipping. 



Standard LSZH USB cables are constructed similarly to the premium line of USB cables: they have 20 AWG power conductors for maximum power transfer, and have 30 micro inches of gold on the contacts to ensure reliable connections through multiple mating cycles. Along with the standard type LSZH cables, L-com also carries a line of its "latching" USB cables with LSZH jackets.  These cables have small latches in the Type A connectors that lock the connector in place.


LSZH USB cables with Latches prove to be especially valuable in high-vibration environments such as in a military vehicle or in a device that is meant to be carried over rough terrain. Don’t overlook endangering personnel and valuable communications equipment by using standard PVC USB cables; LSZH USB cables might be better for your application.


For more information check out our ratings chart below, or this helpful video on cable flammability tests.


USB Flammability Ratings


This Week's Lineup of Bulk Cables

November 21, 2013 at 4:25 PM


If your job or application requires buying cabling in bulk, then you understand that the term “bulk cable” covers a lot of ground. There are several different types of bulk cable, various ways to use them, and multiple avenues to order from.

Bulk CableSpoolAlthough a factory-terminated cable assembly will suit just about any connectivity application, you still want to be mindful of exceptions. Sometimes the connector on a cable is too big to pass through a narrow conduit or too difficult to fish through a wall or a ceiling.  Or the pinning is non-standard, and an off-the-shelf product won't work. Sometimes you won't know the proper length of the cable until you get to your location, so you will be forced to terminate the cable on site. To help you determine what you need, here’s a look at a couple of bulk cable types L-com offers and some ordering advice.


Fiber Optic Cable

fiber cableFiber optic cable is one of the most commonly ordered bulk cable types. Since fiber cable can be run to extreme lengths, it is impossible for anyone to carry factory-terminated cables in all the lengths that may be required.  Also, ordering bulk fiber cable isn’t the same as ordering for standard fiber optic specifications. When ordering fiber optic bulk cable, there are several factors to keep in mind. 

Short fiber cables for patching are generally duplex, with two counts of fiber, or occasionally simplex with one fiber. As you run longer cables or higher counts of cables, it is usually desired to bundle several fibers into a single jacket for convenience and protection when pulling through a conduit.  L-com offers two types of cables bundled in this way: breakout style and distribution style. 

Fiber Distribution cable

The biggest difference between breakout style and distribution style is where the Kevlar strength member is used. In breakout style cables, each internal fiber optic cable has its own Kevlar layer within each jacket.  This can increase the strength of the entire cable and provide additional strength to each fiber if the outer jacket is stripped away for termination.  Usually, due to the thickness of each fiber, breakout style cable has a fewer count of fibers in it compared to distribution style fiber. 


Distribution style cable only has one Kevlar layer around all of the fibers within the outer jacket.  The advantages of this is that the outer diameter of the whole cable is reduced dramatically, so you can fit it in tighter conduits and carry a higher count of fibers in it. The individual fibers are faster and easier to terminate since you don't have to trim back the Kevlar on each fiber cable.


Whichever style works best for you, fiber optic cables are unique in that you do not need to order in specific "put ups" or order lengths. While there is usually a minimum order length, you can order the bulk fiber cable to whatever length you are likely to need.  Note that terminating fiber cables generally requires special training and equipment.


Bulk Ethernet Cabling

Double Shielded: Foil plus Braid - SF/UTP LSZH - 24 AWG Solid Conductor - LSZH Jacket - Category 5E

Often, bulk Ethernet cabling is used in horizontal runs from a server room to individual drop points at workstations.  Because of the sensitivity of the twisted pairs within the cable, it should be spooled carefully in the manufacturer's factory. Once it is pulled off of the spool for use it should not be re-spooled.  For this reason many distributors can only sell the bulk cable at whatever put up it was spooled at originally, which is usually 1,000 feet.  


There is much to know about Ethernet cabling, such as jacket material, shielding and flexibility, but most important is whether the conductors are stranded or solid.  Solid conductors are more popular in horizontal runs because they are much easier to terminate in IDC jacks at the drop points, while stranded conductors are more flexible and best suited for use as patch cables.


There's more...

In addition to the many variations of Fiber Optic and Ethernet bulk cable; there is also bulk cable for USBRG and Low Loss coaxVGA and SVGA  applications and more (all of which L-com carries!).

Shielded Ethernet Cable: Advantages and Disadvantages

November 18, 2013 at 9:08 AM



Cat5e Shielded Ethernet Cable- 26 AWG Stranded PVC Industrial Ethernet Patch Cords - Blue

Shielding Ethernet Data from EMI/RFI


The typical Ethernet cable has four twisted pairs terminated to the eight pins in the clipped "RJ-45" (also, more correctly known as 8p x 8c connector) at either end. The cable used is commonly called "UTP", which stands for unshielded twisted-pair.


If there is an unshielded version, there must also be a shielded version right? That is correct. Today we'll look at STP, or shielded twisted-pair


The Shielding Disadvantages


Shielding is not an automatic choice for every installation. Why? Because although shielding provides the protection that may be necessary for some environments, it also comes with some serious disadvantages.

Shielded Ethernet Cable


The first is weight. A single-shielded Ethernet cable weighs on average about 12% more than an unshielded cable, and a double-shielded Ethernet cable weighs as much as 30% more. That doesn't mean much when you have a single 4oz cable. But what if your building has dozens or maybe hundreds of individual STP cables that run on ladders over a ceiling, under a floor, or behind walls? The combined weight from these cables could be such that they actually damage the rack. 


The second disadvantage is flexibility. In permanent installs, this isn't so much of an issue, though you must be careful when pulling the cable through conduit. But in applications where the cable is attached to something moving, like a robotic arm, a swiveling camera, or tools used by manufacturing personnel, the shield can be a problem. A single foil shield can break and the sharp edges of the cut in the shield would grind against the insulation of the individual wires, eventually cutting into it and shorting it out. Your best bet is to get tight-extruded cables rated for continuous flexing to ensure the maximum lifespan over repeated cycling.


Shielding Options


There are several options available if you need a shielded cable for your Ethernet application:



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