How to Protect Your Equipment During Lightning Season

August 24, 2017 at 8:00 AM

 

No matter how lucky you are, the thought of lightning striking your expensive communications equipment can be a scary thought. Depending on your location, the time of year and your proximity to other buildings, the chances of a lightning strike can be higher or lower, but any lightning strike can be debilitating for sensitive electronic equipment. Both direct and indirect strikes can cause extensive damage that includes loss of data, downtime and the cost of replacement.

 

Electromagnetic fields and earth-voltage spikes caused by lightning can also wreak havoc on electronic power and signal circuits. This can damage the Ethernet, coaxial and telephone lines, or anything connected to the circuits. Even entire campuses can experience long-range voltage spikes that can ruin all electronics connected by the above-ground and below-ground cabling systems that run throughout the campus.

 

There’s no single cure-all method, but lightning protectors are an inexpensive way to help protect equipment in the event of a lightning strike. Here are some of the best solutions to give your equipment a fighting chance:

 

 

Coaxial Protectors – These lightning protectors use gas-filled tubes to discharge electrical spikes before they can cause damage. They are used in both wired and wireless networks to protect radios, communications equipment and anything else attached to coaxial cable, which becomes a target for lightning. They feature popular connector types including N, TNC, RP-BNC and F.

 

Low-PIM Coaxial Protectors – Theses are ideal for use with Distributed Antenna Systems (DAS) because of their low-PIM performance of -150dBc. They feature bi-directional protection and there are no gas tubes to replace.

 

Cat5/5e/6 and PoE Protectors – These protectors ground-out and discharge spikes that can permanently blackout security cameras, switches routers and other critical equipment. They are ideal for 10/100/1000 Base-T Ethernet networks. Some models even feature integral PoE injectors that can deliver remote power to access points, access servers, outdoor routers and other Ethernet IP enabled devices.

 

Telephone/DSL/T1 Protectors – They protectors can prevent your POTS or other telephone system from expensive downtime and are perfect for indoor or outdoor installations. These protectors are available in multiple styles including screw terminal 

and RJ11 options.

 

RS232/422/485 Protectors – These are ideal for protecting RS-232, RS-422 and RS-485 lines. They can also save sensors, control lines and AISG lines from lightning’s damaging effects.

 

To see all the products L-com offers to protect your equipment from lightning, click here.

 

A Cornucopia of Coax

October 29, 2015 at 8:00 AM

 

Do you love endlessly searching for coaxial products to fit your requirements? Is the highlight of your day going from one company to another to get the correct coax solution? If you answered no, we’re on the same page.  If you answered yes, we may be a little concerned.

 

Finding the coax products you need can be a daunting task when you have multiple coaxial applications, need multiple parts or just want the right part the first time. That’s why, when it comes to coaxial products, L-com brings more to the table than just a basic offering, we bring you a cornucopia of coax cables, bulk cable, connectors, adapters and more! Our product line includes everything to address your coax needs and if what you are looking for doesn’t exist, we can make it for you as a custom product.

 

We offer one of the broadest lines of off-the-shelf coaxial products for all of your 50 Ohm and 75 Ohm applications including wireless, video surveillance/CCTV, OEM, Audio and Military/Aerospace. Our coaxial product line features coaxial cables, RF connectors, RF cables, coax connectors, coax adapters, tools and other high quality coaxial products.

 

For wireless connectivity applications, we stock thousands of low loss 50 Ohm antenna RF cable assemblies, pigtails and bulk cable. Our inventory includes both popular and hard to find coax connectors, couplers and splitters for low-loss 50 Ohm applications for use in Wi-Fi networks.

 

If, for some reason, we don’t have what you need, we can make it for you. L-com can custom design cable assemblies, adapters, and almost any other connectivity product to meet your project requirements and we can build them in large or small batches. We even have a handy cable configurator that saves you time by allowing you to design and order your own custom cable assemblies online, including low-loss coaxial and RG-style coaxial cable assemblies.


When it comes to coax, our abundant product line offers everything you need in one place. Click here to see what our cornucopia of coax brings to the table.

 

Tips for Buying Coaxial Cable

August 14, 2013 at 10:00 AM

 

What’s right for your application?

 

Selecting the proper coaxial cable can go a long way toward satisfying the needs of a specific application. Which criteria are most important to the specifying process? There are 4 key points to be considered when choosing coaxial cables:

 

      RG174/U Bulk Coaxial Cable - Flexible Small Diameter 50 Ohm Cable

 

 

 

 

 

 

1. Cable Type

 

There are basically two types of coaxial cables: those with an impedance of 75 Ohms (Ω), used mostly for video applications, and those with an impedance of 50 Ω, used mostly for data and wireless communications.

 

Typical 75 Ω cables are our RG59/U and RG6/U. These cable types are available in 100-, 500- and 1000-foot reels.

 

Typical RG-style 50 Ω cables for data are RG174/U, RG188/U and RG316/U. These bulk cables can be used in applications where cable assemblies must be built in the field. Available in 100-, 500- and 1000-foot rolls, their stranded 26 AWG center conductors result in very flexible cables for tight-fit applications. Additionally, the bulk RG188A/U cable has a Teflon-taped outer jacket to help achieve a 200-degree C operating temperature, and the RG316/U has an extruded FEP outer jacket that helps achieve a 200-degree C operating temperature.

 

50 Ω cables are also available in the low-loss version: 100-, 200-, and 400-series specifically for wireless applications. Low Loss coaxial cables provide far better shielding than their RG style counterparts and are best suited for RF applications.

 

 

2. Operating Frequency

 

Another important consideration is the operating frequency of the signal carried on the cable. As the frequency increases, the signal energy moves away from the cable's center conductor to the cable's shield outside of the conductor, a phenomenon known as the "skin effect".

 

This has a direct correlation to how far the signal can travel over a cable of a certain length, for a given signal frequency and power level. The higher the signal frequency, the shorter the distance traveled.

 

For our full Coaxial Cabling Tutorial, click here.

 

 

3. Cable Attenuation

 

Cable attenuation is the amount of signal loss over a specific distance. In general, the higher the frequency, the larger the attenuation will be. The larger the diameter of a cable's center conductor, the lower the attenuation is.

 

For example, an RG59/U cable with a 14 AWG center conductor can carry a signal (at a specific frequency and power level) about twice the distance as that of an RG11/U cable with a 20 AWG center conductor. It's imperative to know how much cable attenuation is acceptable in your particular application when selecting coaxial cable.

 

 

4. Characteristic Impedance

 

A coaxial cables characteristic impedance is an important parameter that affects the performance of the signal being carried over the cable. Also known as transmission impedance, it is defined as the relationship between a cable's capacitance per unit length to its inductance per unit length. For optimum signal transfer, the cable's characteristic impedance should be matched to the impedance/resistance of the load.

 

RG59A/U Bulk Coaxial Cable - Stranded Center Conductor 75 Ohm Cable
50 Ohm BNC Crimp Plug for RG58 - Amphenol #31-320-RFX
See a Matrix of Data
and Wireless Coax Cable Assemblies for Easy Ordering
Looking for bulk 75Ω cable for audio/video? See it here!
Get Coax Connectors
from L-com and build your own cable assemblies!
 
Quick note: RG-style coaxial cables are not all built the same. Check the specification requirements before you buy, and if you need help contact our technical support.
 

Tutorial on Coaxial Cabling

July 3, 2013 at 10:00 AM

 

 

 

Coax is one of the most venerable cabling standards having been developed for the US military over 50 years ago. Unlike some standards that were popular for a while and eventually became legacy, coaxial cabling is still very relevant and used in a lot of common applications. It is a robust and reliable cable type with no sign of going away any time soon.

 

 

 Types of Coax Cabling

 

As you can imagine, over the years that coax has been around, many variations have been designed for specific applications. We will talk about the Radio Guide (RG) styles and the low-loss styles that were made popular by Times Microwave's LMR® standard. Though there are many other coax options like mini coax, twinaxial and tri-axial, the applications for those have dwindled in recent years.

 

 

RG-style Coaxial Cable

 

The original Radio Guide standard called for a number followed by codes to determine specific aspects of the cable (such as jacket type, center conductor material, etc.). However, today many of the standards have become "soft" meaning that RG58B/U, for instance, may have very different characteristics from manufacturer to manufacturer.

 

Exposed view of a coaxial cable

Most RG numbers refer to cables made with specific diameters (as thicker diameters typically have lower attenuation over long lengths), shielding, jacket type, and dielectric type. The dielectric is important as it can control the "characteristic impedance" of the cable. In general, cables with a characteristic impedance of 50 Ohms are used in data and wireless network applications, and cables with a characteristic impedance of 75 Ohms are used in higher bandwidth audio/video applications.

 

The bottom line about RG-style coax cable: if you need to get a specific type for your application, you should include the characteristics of the cable with your request. The actual standard may have some variations that would make the off-the-shelf product unsuitable for some circumstances.

 

 

Low-loss Coaxial Cable

 

Low-loss cable is almost exclusively used in wireless applications. It is ideal for any antenna-to-radio setup, and is often used extensively in wireless system installations. Low loss cable is often referred to by its series number, such as 200-Series cable, which is usually a rough approximation of the diameter of the cable. The higher the number (ie, 400, 800, etc), the thicker and heavier the cable, and the less attenuation over the length. Because of this, higher series numbers are typically used in cases where the antenna is permanently installed at some distance from the radio. Lower series numbers are used in cases where the antenna is closer, especially in portable setups where the weight of the cable is important.

 

 

Connectors

 

There are a large variety of coaxial connectors, usually designated by a letter or combination of letters. Most coaxial connectors are round or hex shaped, and can come in screw-on, push-on, or twist-lock designs. Be extra careful if you need a connector that is called "reverse polarized" or preceded with the letters "RP". These connectors are similar to the regular polarity versions except that the gender of the connector is reversed, making it unable to mate unless it is with another RP style connector. For a complete list of coaxial connectors with large images, try this coaxial connector chart.

 
If you are in need of coax: L-com has carried RG style coax cable and assemblies for decades, and together with our vast collection of low-loss coax cables it is one of the most comprehensive in the industry.
 

Low Loss Coaxial Cable for Wireless Applications

June 26, 2013 at 10:00 AM

 

Closeup of Low Loss Coaxial Cable Stripped to Show Components

Even in a wireless network, cables and wires are still used to connect components together (access points to amplifiers, amplifiers to antennas, etc). Each component needs cabling to interact.

 

If you are a wireless engineer and need to interconnect components, chances are you are using low loss coaxial cabling. While 50 Ohm RG-style coax is sometimes used, the attenuation is usually too much for any length over just a few feet. This is where low loss coaxial cable comes in.

 

 

Coaxial Cable and RG-Style Coax

 

All coaxial cable works the same way: the signal is run over two "axes" (thus the name). Coaxial technology is one of the oldest signal cabling types, and is still used today for a specific reason: it is robust and can carry a signal very well over a long distance. In general, the thicker the cable, the less "loss" or attenuation of signal there is over the length of the cable.

 

The original standards for coaxial cable were set forth by the US military. These cables used the term "RG" (for "Radio Guide" or "Radio Government") followed by a number to designate the standard. This worked well at the time, but as technology became more and more utilized in commercial and non-military applications, the restrictions of the standard became less rigid (to the point where RG316, for instance, may have very different properties today depending on who manufactures it).

 

 

Times Microwave LMR® Cables

 

No matter who makes the RG-style cables, they have one fundamental problem: the signal degrades over the length of the cable until it is no longer useable. For shorter use in labs or machine-to-machine applications, this is not a problem. But in wireless applications, the signal integrity up until it is broadcast through the antenna is critical.

 

For that reason, Times Microwave Systems developed a low loss version of coax that it branded as its LMR® series coax. The newly-engineered solution offered far lower loss and better RF shielding, making them a much better choice for wireless systems than the RG styles.

 

Outside of Times Microwave Systems' product (the term LMR® refers specifically to Times Microwave Systems product and is trademarked for their use), several other companies now offer low-loss coaxial cables. These generally follow a similar naming convention as what Times Microwave Systems uses: a three-digit "series" number that refers to both the thickness of the cable and the low loss properties.

 

For instance, 100-series low loss coax is thinner and has greater loss than 200-series, which is thinner and has greater loss than 400-series, etc.

Diagram of most common low-loss coaxial cables

Note that with thicker cable factors such as cable weight and flexibility must be considered. However, there are now ultra-flex versions of thicker series like the 400-series that offer similar loss characteristics but are far more flexible.

 

Quick note: L-com has been manufacturing high-quality coaxial cables and components for over thirty years.
 
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