The Low-Down on Low Voltage Wiring
Many of today’s homeowners can’t envision a home without high-speed Internet and Wi-Fi, home automation controls for amenities such as lighting and music and up-to-date security systems with cameras.
That’s why many homebuilders are making installation of structured cabling in new construction standard or offering it as an option. And while some of the basics are the same, installing low voltage wiring is a whole different ballgame. Whether you’re managing an electrical project or you’re a homeowner, this guide will help you gain a better understanding of how low voltage wiring works and how an electrical contractor can help.
Low Voltage Wiring in a Nutshell
So, how does installation of structured cabling differ from installation of standard electrical cabling? Most wall of cable outlets run 120V or 240V of electricity. But low voltage wiring doesn’t carry the same current as the power outlets, fixtures and switches typically installed in homes. Low voltage wiring is designed to carry 50 volts of electricity or less. Common low voltages are 12V, 24V and 48V.
Low voltage wiring is often used for Smart doorbells, telephones, garage door opener controls, heating and cooling thermostats, landscape lighting, alarm system sensors and controls (security system cameras, motion sensors), audio-visual wiring (surround sound audio systems, cable television, intercom systems), internet network and Wi-Fi, and LED or low voltage lighting.
The infrastructure on which low voltage wiring operates is called structured cabling. A structured wiring system is built on a separate network from most of a home’s wiring. In most cases, the home’s main electrical system is installed first, followed by the low voltage wiring.
Optimal performance of a structured cabling system is dependent upon a good design. A good design considers airflow and cooling issues, allows for redundancy, chooses the correct cabling for the job, and plans the cabling patch ways. Some of the more common types of cables used in low-voltage wiring include:
- Unshielded Twisted Pair (UTP) cable — Cat 6 or 6a cables are the ones most often used in homes today.
- Fiber optic cable — Used for long distance runs. It’s difficult to work with and requires specialized crimping tools and connectors.
- Speaker wire — Used for whole-house audio and home theater applications.
- Thermostat wire
- Coaxial cable (coax) — The most common types used in a home are RG-59/U (.64mm core and a single shield), RG-6/U (1.024mm core with a double shield) and /RG-6/UQ (1.024mm core with a quad shield.
- Security system wire — Commonly in 18 and 24AWG, with either two or four conductors.
A structured cabling system is simple, efficient, forward adaptable and organized. Specific wires can be quickly pinpointed. It’s also flexible and easy to alter or make additions to. It can carry data at high rates while reducing power and maintenance costs.
Here are some of the most important details electrical contractors will need to learn before installing structured cabling systems.
You can’t pull low voltage wire the same way you pull electrical wire. Low voltage wire is very fragile. Rough handling can damage it, pulling out the twist, and affecting cable performance. A maximum of 25 pounds of pull strength is recommended, although each manufacturer has its own standard which you should follow.
Another important thing to note is that low voltage wire, such as fiber optic cable, can’t bend at a 90-degree angle. If you need to turn it in a different direction, you’ll have to form a loop. Again, look at the manufacturer’s standards to determine the maximum radius of the loop. Cable fibers are prone to kinking or breaking, which can degrade the signal.
Low voltage wires should be installed a foot away, at a minimum, from the home’s main electrical wires, running parallel with all the cabling. The higher voltage on electrical cables can create signal interference that may affect the data cables. If you can’t avoid installing low voltage wires across electrical wires, they should be installed at a 90-degree angle. And, typically, copper cabling shouldn’t exceed 100 meters, although there are some exceptions.
A Great Growth Opportunity
The global structured cabling market is expected to reach $17,181.2 million by 2022. The market is especially robust in the U.S. due to the high demand for Internet connectivity and also because so many technology giants are headquartered here.
This creates a great financial opportunity for electrical contractors. While there is fierce competition from other cable installers such as electronic system contractors, alarm system installers, and home entertainment installers, electrical contractors are better-positioned in many ways to take advantage of this lucrative opportunity.
Why? General contractors like to work with companies they’re familiar with and companies that they’ve enjoyed a good working experience with on prior jobs. General contractors know the importance of relationships built on trust. Plus, electrical contractors are a major part of the project and are already on the jobsite installing the main electrical components. They can’t be replaced by an alarm installer, for instance.
Another reason general contractors prefer to give all the cable installations to electrical contractors comes down to the bottom line. Having an electrical contractor as a single point of contact instead of dealing with multiple installers can save a general contractor up to 20 percent on the electrical installation cost of the job.
Should You Jump on the Bandwagon?
Just because it would be beneficial to general contractors, doesn’t necessarily mean electrical contractors should jump on-board. As we’ve seen, installation of the main electrical system is very different from the installation of the low voltage system. Without proper training and experience, taking on this new opportunity could lead to a failed network. And that could put a black mark on your company’s professional reputation. It also requires a shift of focus: Your company will have to become more customer-service oriented when dealing with customers.
Low voltage wiring operates under a different set of rules and governing bodies (IEEE, ANSI, EIA, TIA and BICSI) than electrical wiring, which follows the standards set by the NEC. Low-voltage licensing varies from state to state and even city to city in some states.
The structured cabling industry also faces competition from other home networking technologies such as power line communication and wireless systems. Both are less expensive to install and require a minimum of professional installation expertise.
Still, structured cabling is a business opportunity that electrical contractors should not overlook. It will require licensing, insurance, professional certifications and the ability to test and certify the system installation.
But, with the proper training and accreditations, electrical contractors can successfully compete with other cable installers.
If you’d rather dip you toes in the water than plunge right in, consider partnering with a low-voltage contractor as a subcontractor. That way you can learn the ropes before making a decision. The role and responsibilities of low-voltage contractors have expanded to encompass system designer, integrator and application troubleshooter as well as installer. Low-voltage contractors may be very willing to pass the installation part the job on to electrical contractors. It could be a win-win for everyone.
Every company has to make the decision for itself. But, in the future, electrical contractors with structured cabling experience and education will have a strong competitive edge over electrical contractors who don’t have this tool in their toolbox.