Aerial cable installation and what you need to know

Aerial cabling has been around forever but this method does have the highest risk of taking a crap on you due to natural disasters, vehicle accidents, lightning strikes, falling tree limbs and so on. Aerial cable runs also detracts from the aesthetic appearance of the property and installation hardware will damage the exterior of your building. If an aerial cable installation is right for you some advantages will be, fast installation and easy access for maintenance. Check your local ordinance first, your aerial cable run may be restricted.

Your planned route must provide enough stabilized ground for your installation vehicle to be supported properly during the installation and later when maintenance is required. One of the most complex installations that comes to mind for us is a ski lift install requiring a PE38 cable be ran to the top of the mountain.

Here's an example of a PE38 cable from our YouTube Channel.



Pole placement should take into account your future cable capacity needs, pole type class, storm load requirement, optimum span lengths and minimum height clearance. Cable must also maintain sag clearance.

Class numbers are assigned to pole strengths with the strongest being class 1 and the weakest being class 10. Marked poles should indicated their class, species of timber, preservative treatment, and footage. If a pole is installed in a sloping ground, the depth of the pole set must be increased over the depth used for flat ground installation. An outside plant designer should know about the three definitions of pole loading: transverse storm loading, vertical loading and bending moments.

Your aerial cable suspended strand is available in two types, Class A for general use and Class C for corrosion prone areas. Proper selection should be made for pole to pole installation. The selection of span length should follow these guidelines: * Strand tension should not exceed 60% of breaking strength under storm loading conditions. * Strand tension should not exceed 70% of breaking strength with cable in place and a 300 pound load concentrated at mid span. * Sag should not exceed 10ft at a 60 degree Fahrenheit temperature, without any wind loading.

A self-supporting cable span length is limited by the simultaneous application of the two previous factors. Self-supporting cable is a special construction in which the sheath covers both the support strand and the telecom conductors. When tensioning a self-supporting cable, special clamping devices are required for the come-along to avoid cutting the polyethylene strand covering.

In almost all cases, a pole will require some type of guying hardware, which is available as side, head, anchor, pole to pole, or pole to stub guy.

You can place an aerial cable from a stationary reel or a moving reel in either of two ways. The first way, temporary pulleys or J hooks are installed at each pole, then the truck winch is fed through the pulleys, or hooks, and attached to the end of the cable.

The second way is the end point of the cable is attached to the first pole and the rest of the reel is moved to the next pole, etc. Temporary pulleys or J hooks are not needed, because the cable is attached to each pole as it is unreeled.

So maybe your thinking about direct burying your cable instead. Check out our other blog post on direct burial cable installation tips.

You might want to consider working with a outside plant designer, there is a lot of math and science involved in this type of installation. Maybe even make an investment into a OSP design reference manual to help you out.

Special thanks to Electrical Construction and Maintenance.


Any questions? Comments? Leave them below. Thanks!

"By Mercy Salinas"

25 pair and 100 pair Cat5 Burial Cable Overview

With the flood of wire and cable coming in from overseas you have to keep a good eye out on making sure that you select a high quality cable so you can get a solid return on investment for your network.

Over the past few years I've seen many problems with overseas cables, such as the cable specifying that it was a 24 gauge but after the installation contractor installed it and had problems with making a proper connection we found out that the cable was actually a 26 gauge cable. It's hard to notice since the colored insulation is over the copper conductor. This is such a common issue with overseas copper cable that I feel like it's common practice. It's a dirty trick that enables overseas manufactures to offer a lower price for a false product. (Cool book, poorly made in China ).

Another dirty trick that gets pulled on the consumer is copper clad aluminum cable. Because the cost of aluminum is lower versus copper, these cables are lower in price and you may not realize you have purchased this cable until after your installation is complete and your cable tester won't certify that new cable you just installed.

I always recommend purchasing a cable from a manufacture that has been in business before the year 2000. These types of manufactures have been established and many fall under Trade Agreement Acts for the procurement of goods for federal contracts with the United States Government.

Now that we know what to look for let's look at one of the most popular selling Cat5 burial cables.

This cable is most commonly installed in outside plant installations and is your broadband backbone. The Essex Megapic cable provides an extension of the LAN beyond the premises. Installed in direct burial, underground and lashed aerial applications.

Available in a 25 and 100 pair count and because your purchasing from Superior Essex you can count on quality, made in America and Essex has been making cable since the 1930's out of Detroit.

Let's get a better look at the cable from our YouTube Channel.

  

When making an investment in your network, our 13 year track record of selling this cable gives us comfort knowing that we are offering a quality solution that will meet all your needs.

You can order 04-097-31 by the foot. If you have any comments leave them below.

Thanks.

"By Mercy Salinas"

Outdoor Aerial Wire and Cable Installation - Moving Reel Method

Customers purchasing our many different types of outdoor wire and cable commonly ask how to lash cable to a messenger wire. One of the most common ways to do this is by using the moving reel method.

This method is used when reel carrying vehicles can drive most of the route. This method may be used when placing cable on a suspended strand or to an existing lashed cable and strand. Check out this cool lashing machine in action!


Each time a pole is reached the pulling stops. The cable guide (just in front of the lasher), and lasher get disconnected and moved past the pole. An expansion loop to the messenger is formed as temperature changes contracts the steel more then cables. Example below.


Before you get started let's go over some precautions.

* All personnel must be familiar with OSHA Occupational Safety and Hazard Act regulations.
* Follow the National Electrical Safety Code (NESC) for all installations.
* Cables installed near high voltage lines should be grounded.
* Cables that contain a corrugated steel tape should be grounded.
* The steel messenger shall be grounded.
* Make allowances for changing sag of the steel messenger wire in various weather conditions. Steel  messenger wire will expand and increase sag in warm weather.
* The steel messenger should be kept on one side of the poles (avoid zigzagging from one side of the pole to the other).
* Carefully inspect reels for imperfections such as broken flanges, cable crossovers, nails or anything that may cause damage as it is payed out.
* Follow the cable bend radius. Coax, phone and fiber wire and cable will differ.
* Never during the install should cable experience sags, bends and twist. A reduction in the cables transmission characteristics may not reveal itself till after installation.
* Do a pre-survey for splice locations, slack locations, cable storage requirements and possible obstructions like trees, roadways etc.
* You may want to consult an outside plant engineer.

As you can tell it sounds easy but lots of precautions do go into an installation of this type. I can hear my mother now, "Don't forget to put your helmet on!"

Thanks to Prysmian, OCC and Commscope.

"By Mercy Salinas"