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Step Aside, Ma Bell

New Phone System Options Create Opportunities for Custom Installers

Consumer demand for home technology is still a burgeoning market, and this trend does not exclude home telephone systems.

When most people think of home communications, what first comes to mind are cordless phones, answering machines, a voice mailbox from your local service provider and maybe even an old-fashioned built-in wall intercom. Thankfully, times have changed. Todays home telephone system typically starts at four lines, eight stations and two analog ports for connecting equipment such as fax machines. It replaces the need for a separate wall intercom system and includes voice messaging that is individualized for each person in the home without adding a monthly fee for every voice mailbox. It also connects with door phones, controls the security gate, and adds features like placing calls on hold, paging people throughout the house and even transferring calls to other extensions or to a voice mailbox.

Cabling and Wiring Plans. With new technologies also comes a change in installation practices. Lets consider often-overlooked steps when cabling a home for new telephone system technology.

Where will the equipment be located? In a custom home, its hard to create a place for a phone system if it was not initially planned. A phone system requires approximately a 4 x 4-foot location on a wall. We call this a main distribution frame or MDF. Because phone systems are not built on 16-inch centers, they usually require a solid wood backboard so that you can mount all required hardware.

All cabling today needs to be home run cabling to the MDF. For some old intercom systems and single-line telephones, the cable was looped between each location with only one connection to the telco line provider. One or possibly two cables will need to be run from the MDF to where the phone company plans on putting their entrance and lightening protection box on the homes exterior. This cable should be four-pair Cat-5 or Cat-6 cable, or the highest-grade cable made for voice. You may need a separate four-pair Cat-6 cable for the home connection to the Internet run to the MDF.

If cabling for a data network, your data cables could all terminate at the MDF as well, thus allowing this to be the place where you install the home Internet router and data switch. This helps futureproof the home as technology changes. To go the extra mile, run a conduit between the telcos outside location and the 4 x 4-foot phone system area. This will allow you to some day change the cable out to fiber as technology progresses. With the conduit, you can change the cable without tearing up walls or running exposed cable.

Todays digital telephone system can run on Cat-3 cable, but because most homes are still standing for well over 50 years it makes sense to install the latest technology. Choices for voice or telephone systems cables are Cat-3, Cat-5, Cat-5e and Cat-6. Cat-5e is the preferred choice for voice as it can easily be used for data or Voice over IP (VoIP) in the future. This is important because most homes are not built like most businesses. To re-cable a home means tearing up walls; better cabling can prevent that from being an issue for years to come.

Most digital telephones use two wires in a cable, some use four wires and IP phones can use all eight. Because of these differences, here are some more good practices an installer should follow:

Never cut unused pairs of wire off at the jack end. Instead, neatly wrap them around the outside of the cable, enabling future changes, for example, to an IP phone system.

When possible, use a Cat-5e or better patch panel to connect head-end cables. This will allow homeowners to easily relocate telephones and accommodate an easy upgrade path to the next generation of technology without re-wiring. At the head end always terminate all cable pairs in the proper color code order. If you use 66 blocks or 110 blocks, still terminate all cable pairs and include a two- or three-foot service loop, allowing re-termination for future technologies.

Upgrading to a newer technology like a VoIP telephone system will soon have economies of scale that reach the housing market. If your cabling infrastructure is implemented properly now, accommodating this upgrade will only require installing a new insert at the jack end by terminating those extra wires and putting in the new phone system at the head end along with new phones. The beauty of preplanning the wiring will eliminate the need to rip up the house to put in new wire.

Proper color code on a four-pair cable is:

Pair 1 – White wire with blue stripe/blue wire with white stripe.
Pair 2 – White wire with orange stripe/orange wire with white stripe.
Pair 3 – White wire with green stripe/green wire with white stripe.
Pair 4 – White wire with brown stripe/brown wire with white stripe.

Labeling your cable on both ends, labeling the jack insert to match the cable label and leaving the homeowner with an as built drawing of the wiring that references the labeled endpoints will make it easier for the homeowner to maintain the system.

General Site Considerations. It is critical to locate the best acceptable site for the common equipment such as key service unit (KSU), boards, etc. Consider these points for a KSU mounting site:

Wall Mounting. KSUs are designed for wall mounting. It is recommended that a minimum of one-half-inch plywood backboard be firmly mounted to the wall and that the KSU and MDF be mounted to the backboard.

Dedicated Access to AC Power. The location must have access to a dedicated 110-Volt AC (10 percent), 60 Hz, and single-phase circuit with a circuit breaker or fuse rated at 15 amps. A three-wire parallel blade grounded outlet should be within approximately four feet of the KSU.

Power Line Surge Protection. The AC outlet should be equipped with a power surge protection device or an uninterruptible power supply (UPS). Systems using such devices are more resistant to damage from power line surges than unprotected systems. Power line surges often occur during normal operations and during violent thunderstorms. Installation of a surge protector meeting the specifications described below may prevent or minimize the damage resulting from power line surges. The isolation transformer/surge protector should be a 15-amp, self-contained unit that plugs into a standard grounded 117V AC wall outlet. The wall outlet must be designed to accept a three-prong plug (two parallel blades and a ground pin). The protector should be fast and capable of protecting transients greater than 200 volts. A UPS enables the homeowner to use the telephones when the power is out. You should also have at least one power failure phone connected to a line ahead of the system for power outages that may last longer than the UPS is rated for.

Lightning Protection. The systems should provide secondary protection per UL 1459 specifications. Primary protection circuitry is the installers responsibility and should be installed per National Electric Code (NEC).

Grounding. To ensure proper system operation and for safety purposes, the location must have access to a good earth ground, such as a metallic cold water pipe without non-metallic joints. The ground source should be located as close as possible to the system. A metallic cold water pipe usually provides a reliable ground. Carefully check that the pipe does not contain insulated joints that could isolate the ground. In the absence of a cold water pipe, a ground rod or other source may be used. A #12 insulated AWG or larger copper wire should be used between the ground source and the KSU. The wire should be kept as short as possible (recommended 25 feet or less).

When grounding the system, be sure to remove about one and half inches of insulation from both ends. Attach one end of the wire to the ground lug on the KSU by inserting the wire under the lug screw and then tighten the screw securely. Next, attach the other end of the wire, as appropriate, to the ground source. Then, take a DC resistance reading and an AC volt reading between the chassis ground point (cold water pipe) and AC ground (third wire AC ground). The limit is 5V AC and 5 Ohms DC resistance. If a higher reading is obtained, choose a different chassis ground point and repeat this step until a suitable ground point is found.

Environment. The system should be located where it is well ventilated with a temperature range of 68-78 degrees F and a relative humidity range of 5-60 percent (non-condensing). A bad place is the laundry room, because of the amount of dust that accumulates there.

FCC Regulations. Because phone systems come in all shapes and sizes, one of the most important things to remember is to look for a solution that is FCC-approved for Class B home installations. This FCC regulation has limits for RF radiation of the digital device. The test differences for RF radiation are approximately three times closer for Class B home use than for Class A commercial use.

Dont Forget About Customer Service. Besides completing a seamless installation job, communicating with the homeowners and training them to properly utilize the phone system will elevate your business to providing the best customer service. You may have to return to the home several times to get the job right.

Remember to give at least one copy of all user guide material for each member of the family and thoroughly explain their warranty. Provide them with information that will make it easy for them to know who to call for service, adds, moves, or changes, and warranty work. Let them know all of their phone numbers (home systems usually have more than one number). Advise them of their fax number and teach them how to use the one phone that was set-up in case of power outages. Be their partner with this new technology, teach them all the features, set up their voice mail out dial and help them with their greetings to insure things are done right from the start. Finally, suggest or provide a labeling program so they know how to change the labels and features on the buttons of their phones and can customize the system to their own needs.

Owning a telephone system is empowering for a homeowner. Many benefits are now under their control, such as having access to features and capabilities that were typically provided by the telephone company. Gone are the extra monthly recurring charges for features like voice mail (now each household member has a voice mailbox with a visual/audible indication on their phone), call waiting, call forwarding, conferencing and more. Once the homeowner is sold on the benefits of adding a phone system to their electronics collection, your job is to ensure that the latest installation practices are incorporated to meet the demands of this newer home technology.

Todd Lindsey is general manager of Vodavi Direct, a telephone system sales, installation and service company ( in Phoenix, Arizona.