Keeping Ahead of the Material Curve
By Deane Myers
In today’s volatile times, manufacturers are waging war against the rising
costs of raw materials, packaging, freight and production overhead. These costs
have an impact on the price of the materials used in a quality low voltage
installation. To make matters worse, residential construction, a savior for many
installers, has refused to be the leader it once was. It goes without saying that
we as wire and cable manufacturers have a goal to supply a quality product at a
competitive price. But we also have a responsibility to educate our customers on
the cable types that will help reduce cost and improve installation quality. Below
are several tips that may help add to the bottom line of your next sound, video or
CCTV job.
The last few years have seen a huge growth in sound installations. What
was once a niche business for integrators has now become a great revenue
source for security firms, builders, and electrical contractors. Since sound
installations come in many shapes and sizes, the size of the cable or gauge, is
very important. Most equipment manufacturers do a pretty good job of specifying
an acceptable line loss and its corresponding gauge size. If you feel it is
necessary to bump up the gauge size for future expansion, be aware that a
bigger size conductor costs more money and may be unnecessary for the
application. Most sound cable conductors are stranded and stranding counts can
vary. High stranded cables may be easier to install through a raceway or conduit
and let’s face it saving on installation costs is very important. However, if you
have an open pathway with limited twists and turns, a small stranded conductor
will save you a few dollars on the material side. The higher the stranding, the
higher the cable costs. Choose the one that is suitable for the installation and
the most cost effective.
Innovations in cable jacket design have also had an impact on the price of
cable. Pressure extruded jackets fill in the niches between the conductors
making a durable product which is quicker to install and easier to pull without
breaking. Extruded jackets also protect the cable from “staple shorts”. Staple
shorts can occur when the conductors are crushed against each other during
installation. These types of shorts are difficult to locate and repair. The
traditional sound cable construction is made with a “tubed” jacket. These easy to
strip jackets are extruded loosely around the conductors. They may require a
little more care to install but are usually adequate for hazard-free installations.
Remember, a quick trouble-free job can lead to a great costs savings. Extruded
jackets with high-flex stranding may cost more but have an installation labor
savings. Tubed jackets with low stranding are less expensive but are slightly
more difficult to install.
Coaxial cables for CATV, CCTV, and video are one of the most
misunderstood products in the magic land of wire and cable. The RG and RG/U
numbers designate the size and type of coax. RG6 is the popular in-wall solution
for many CATV and satellite installations. Check with the manufactures
specification to determine the proper shield and conductor type. These days the
popular options are copper-covered steel or bare copper conductors and dual
(two) or quad (four) shield coax. Since high frequencies tend to travel on the
outside of the conductor, copper covered steel conductors are sufficient for many
applications. However, solid copper conductors have become popular with
recent satellite services. These new services require the conductor to supply
power to the LNB. A copper covered steel construction has too much resistance
for this application. A little investigation before the installation will save a whole
lot of trouble later on.
CATV and satellite coaxial cables always employ a 100% foil and variable
percent braid combination. The foil shield is most often an aluminum backed
mylar that is wrapped 100%. The braids can be aluminum, tinned copper, or
silver with 20-95% coverage depending on your budget. Many metro areas have
standardized on a RG6: 100% foil/60% aluminum braid/100% foil/40%aluminum
braid quad shield coax. However, some rural providers still work with dual shield
products that are more cost effective. A complex shield has a higher cost but
better signal support. Before the installation, check with the local provider for the
minimum cable requirements.
Be aware of the difference between CCTV and CATV coax. Most CCTV
installations require a solid copper conductor with a 95% braid or better.
Installing the incorrect product will result in a bad signal and void the
manufactures warranty. It may be an advantage to install a coax with 100% foil
shield and a 95% tinned copper braid. By doing so, the cable will support not
only low frequency CCTV but also higher frequency CATV and precision video
transmissions.
Material escalation is often an intangible that causes prices to rise in a
volatile market. Take the time to thoroughly investigate you installation
application and find a quality, cost effective solution to keep ahead of the material
curve. ▲
About the author: Deane Myers is a Regional Sales Manager for Coleman
Cable Inc. located in Waukegan, IL. Coleman Cable, Inc. is a leading
manufacturer and innovator of wire and cable products, servicing the
electrical, electronic and automotive markets. With extensive design and production
capabilities and a long-standing dedication to customer service, Coleman Cable, Inc. is
the preferred choice of cable and wire users throughout the world.