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Table Of Contents
Preparing for Installation
This chapter recommends general safety guidelines to follow and identifies requirements to meet before going to a subscriber site to install a Cisco CVA122/CVA122E Cable Voice Adapter. For safety and regulatory information, see "Regulatory Compliance and Safety Information."
Warning
Only trained and qualified personnel should be allowed to install or replace this equipment.
The chapter includes the following sections:
Safety
This section describes the general, electrical, and electrostatic discharge guidelines that should be followed when installing the Cisco CVA122/CVA122E Cable Voice Adapter.
Warnings and Cautions
Follow these guidelines to ensure general safety:
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Install the Cisco CVA122/CVA122E Cable Voice Adapter in compliance with national and local electrical codes:
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In the United States: National Fire Protection Association (NFPA) 70, United States National Electrical Code.
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In Canada: Canadian Electrical Code, part I, CC22.1.
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In other countries: International Electro-technical Commission (IEC) 364, part 1 through part 7.
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Ensure the shield of the coaxial cable is connected to the grounding system of the residence or building as close to the point of cable entry as practical. In the United States, the cable system must be in accordance with Article 820-40 of the National Electric Code.
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Keep the work area clear and dust free during and after installation.
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Keep tools and other components away from walk areas.
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Do not wear loose clothing, jewelry (including rings and chains), or other items that could get caught on the cable voice adapter. Fasten your tie or scarf and roll up your sleeves.
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Use the Cisco-provided power supply and power cord to connect the Cisco CVA122/CVA122E Cable Voice Adapter to its power supply and the power supply to the power outlet.
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Operate the Cisco CVA122/CVA122E Cable Voice Adapter in accordance with its marked electrical ratings and product usage instructions.
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Always unplug the power cable before installing or removing a cable voice adapter.
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Do not work on the system or connect or disconnect cables during periods of lightning activity.
Electrical
Follow these guidelines when working with electrical equipment:
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Disconnect all power and external cables before installing or removing a cable voice adapter.
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Do not work alone when potentially hazardous conditions exist.
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Never assume that power has been disconnected from a circuit; always check.
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Do not perform any action that creates a potential hazard to people or makes the equipment unsafe.
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Never install equipment that appears damaged.
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Carefully examine your work area for possible hazards such as moist floors.
In addition, follow these guidelines when working with equipment that is disconnected from a power source, but still connected to cable wiring.
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Never install coaxial wiring during a lightning storm.
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Never install cable jacks in wet locations unless the jack is specifically designed for wet locations.
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Never touch uninsulated cable wires or terminals unless the line has been disconnected at the network interface.
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Use caution when installing or modifying cable lines.
Electrostatic Discharge
Electrostatic discharge (ESD) damage, which occurs when electronic cards or components are improperly handled, can result in complete or intermittent system failures. The Cisco CVA122/CVA122E Cable Voice Adapter consists of a printed circuit board that is housed in a shielded enclosure. Electromagnetic interference (EMI) shielding and connectors are integral components of the enclosure. Although the enclosure helps protect the boards, use an antistatic strap whenever handling the Cisco CVA122/CVA122E Cable Voice Adapter. This will minimize the possibility that ESD damage can occur to the internal boards by touching the external connectors.
Following are guidelines for preventing ESD damage:
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If you use an ESD wrist strap or ankle strap, ensure that it makes good skin contact and that the equipment end of the ESD strap is attached to an unfinished surface of the Cisco CVA122/CVA122E Cable Voice Adapter.
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Always place the cable voice adapter on an antistatic surface or in a static shielding bag. If you are returning the item to the factory, immediately place it in a static shielding bag.
CautionFor safety, periodically check the resistance value of the antistatic strap. The measurement should be between 1 and 10 megohm (Mohm).
Site Requirements
Before going to a subscriber site to install the Cisco CVA122/CVA122E Cable Voice Adapter, verify that the following have been done:
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Ensure that a coaxial cable connection is run from the cable TV trunk to the subscriber building or residence.
Note
Cisco recommends that a dedicated (new) CATV cable drop be run from the grounding block directly to the Cisco CVA122/CVA122E Cable Voice Adapter. If such a drop is not available, careful qualification of existing cable is often necessary. Cable ground should be connected to the grounding system of the building or residence as close to the point of cable entry as practical and according to the local and national electrical regulations (for the United States, see the National Electrical Code Section 820-40 guidelines for proper grounding).
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Verify that each subscriber site is characterized at the headend to support upstream transmission and meets DOCSIS upstream and downstream RF requirements. Observe procedures in the NCTA Recommended Practises for Measurements on Cable Television Systems. Also see the "Cabling" section.
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Some sites specify that high pass filters must be installed on every tap drop that does not carry upstream data, voice, or IPPV services.
Note
Installing a high pass filter between the cable voice adapter and the headend will prevent the cable voice adapter from connecting to the headend.
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Ensure that all required headend routing and network interface equipment is installed, configured, and operational. Ensure that DHCP, Cisco IOS images, and configuration files have been created and pushed to appropriate servers such that each Cisco CVA122/CVA122E Cable Voice Adapter, when initialized, can transmit a DHCP request, receive an IP address, obtain TFTP and TOD server addresses, and download a configuration file (and/or updated software image) in compliance with DOCSIS and the procedures in place for your network.
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Ensure that each subscriber site meets the operating requirements specified in the "Site Requirements" section.
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Ensure that all supported equipment at a subscriber site—PCs, telephones, modems, FAX devices, Ethernet hub, and USB hub—is installed and operational. Ensure telephones at subscriber sites support touch-tone (DTMF) dialing.
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Verify that all PCs at all subscriber locations meet the minimum computing requirements. If using USB connectivity, verify that the USB driver software has been installed; otherwise, verify that Internet connectivity is set for the Ethernet interface. See the "PC Subsystem" section for procedures to verify TCP/IP and DHCP PC settings when onsite.
Each service provider has its own recommendations and requirements for the CPE devices connected to its network. However, at the very minimum a PC should meet the requirements listed in Table 2-1.
Table 2-1 PC Minimum Requirements for the Cisco CVA122/CVA122E Cable Voice Adapter
Ethernet Connectivity USB Connectivity Operating System1Windows 95, Windows NT, Windows 98, Windows 98 Second Edition, Windows 2000, Windows Millennium
Windows 98, Windows 98 Second Edition, Windows 2000, Windows Millennium
Processor33 MHz 486 processor (75 MHz Pentium or greater is recommended)
75 MHz 486 processor (Windows 98)
150 MHz Pentium processor (Windows Millennium),
133 MHz Pentium processor (Windows 2000) Memory16 MB
24 MB (Windows 98), 32MB (Windows Millennium), 128 MB (Windows 2000)
Internet SoftwareInternet browser
Internet browser
Networking HardwareEthernet network interface card (NIC)
USB-capable computer
Networking CableStraight-through 10Base T Ethernet cable with RJ-45 connectors2
Host-to-device USB cable (type "A" to type "B")
Networking SoftwareEthernet software driver and TCP/IP networking software (typically supplied with the Ethernet network card)
USB software driver and TCP/IP networking software2
ConfigurationDHCP enabled ("Obtain an IP address automatically")
DHCP enabled ("Obtain an IP address automatically")
1 The service provider might support other types of PCs and CPE devices for network connectivity. At the minimum, these CPE devices must meet the following requirements: 10Base T Ethernet connectivity, TCP/IP networking software, and the ability to obtain an IP address using the DHCP protocol.
2 Supplied with the Cisco CVA122/CVA122E Cable Voice Adapter.
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Ensure that you bring sufficient cables to connect all devices at all subscriber locations. For simultaneous TV and computer usage at a subscriber site, obtain cable splitters and directional couplers as appropriate to install when you install the cable voice adapter.
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The Cisco CVA122/CVA122E Cable Voice Adapter automatically obtains its IP address from the headend DHCP server at power-up. Typically, the PCs at the subscriber site are also configured to use DHCP to obtain their IP addresses; if this is not the case, obtain the static IP addresses for each PC from the applicable system administrator, along with the appropriate gateway and DNS information.
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If supporting VoIP devices, obtain the phone numbers and/or IP addresses that the service provider has assigned to each of the voice ports on the Cisco CVA122/CVA122E Cable Voice Adapter.
Environmental
"Technical Specifications," lists the operating and nonoperating environmental site requirements for operation of the Cisco CVA122/CVA122E Cable Voice Adapter. The values given indicate the minimum and maximum values allowed for the cable voice adapter's operation, but if a measurement approaches the minimum or maximum of a range, it could indicate a potential problem. You can maintain normal operation by anticipating and correcting environmental anomalies before they approach a maximum operating range.
CautionFor proper airflow, keep the top, sides, and back of the cable voice adapter clear of obstructions and away from the exhaust of other equipment.
Power
The Cisco CVA122/CVA122E Cable Voice Adapter does not contain a power switch. After the unit is installed and powered on, it is intended to remain connected to the network and CPE devices during normal operations. Before plugging the unit in, verify that the power source is within the values given in "Technical Specifications" (Table A-1, "Cisco CVA122/CVA122E Cable Voice Adapter Physical Specifications").
Note
The same power supply supports both domestic (U.S.) and international operation. Different power cords are required, however, depending on the country of operation.
CautionUse only a Cisco-provided power supply and the appropriate power cord for the country of operation. Using any other vendor's power supply or an inappropriate power cord can cause loss of data or permanent damage.
Warning
This equipment has been designed for connection to TN and IT power systems.
Cabling
When running the coaxial line from the cable TV trunk connection to the subscriber site, consider the issues of electromagnetic interference (EMI), coaxial cable quality, and distance limitations for signaling, as described in the following sections.
Note
See "Connector and Cable Specifications," for the specifications for the Ethernet, telephone, USB, and power cables.
Interference Considerations
When wires are run for any significant distance in an electromagnetic field, interference can occur between the field and the signals on the wires. This fact has two implications for the construction of plant wiring:
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Bad wiring practice can result in radio interference emanating from the plant wiring.
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Strong EMI, especially when it is caused by lightning or radio transmitters, can destroy the signal drivers and receivers in the Cisco CVA122/CVA122E Cable Voice Adapter, and can even create an electrical hazard by conducting power surges through lines and into equipment. (Review the safety warnings in the "Electrical" section.
Note
Category 5 data wiring and telco wiring is much more susceptible to EMI than high-grade well-shielded coaxial CATV cable.
If wires exceed recommended distances, or if wires pass between buildings, give special consideration to the effect of a lightning strike in your vicinity. The electromagnetic pulse caused by lightning or other high-energy phenomena can easily couple enough energy into unsaddled conductors to destroy electronic devices. If you have had problems of this sort in the past, you might want to consult experts in electrical surge suppression and shielding.
Coaxial Cable Quality
CATV coaxial cable quality can vary dramatically at each installation site. Poor insulation, improperly installed additional outlets, the condition and length of the cable's center conductor, and the quality of the cable can negatively affect the connectivity and performance of the cable voice adapter for digital data transmission. Coaxial cable tolerances for the transmission of two-way digital data are much lower than the tolerances for the transmission of downstream-only video. Coaxial cable used to carry two-way digital data must be of very high quality.
Note
A 5 dB reduction in signal quality for analog downstream video might cause a slight degradation of picture clarity, which might or might not be noticeable to a subscriber.
A 1 dB reduction in signal quality for digital data might completely disrupt service to a cable voice adapteruser.Check the cables for general quality level, tears or cuts in the insulation, insulation that is at least 80% braid with foil, a broken or bent center conductor at the conductor ends, the length of the center conductor, and splitters or amplifiers that have been added to extend video connectivity at the installation site.
Note
The center conductor should extend 1/8 inch (3.2 mm) beyond the end of the conductor.
Tips
Cisco recommends that you replace any cable that is in question and begin the installation with clean, two-way digital data transmission media. If the cable is of high-quality and was recently installed, replacing the connectors with high-quality connectors can also improve performance and eliminate future service calls.
CautionIf you replace a connector, be careful not to score the center conductor. A scored conductor can reduce or impair performance for channels broadcast between 550 and 860 MHz. If the center conductor is too short, signals between 5 and 42 MHz might be affected.
Distance Limitations
The size of your networks and the distances between connections on the CATV network can affect the successful installation of a Cisco CVA122/CVA122E Cable Voice Adapter, which must be within 100 miles of the CMTS. This distance can also be defined in relation to the speed of light through the transmission network as being less than 2 msec from the CMTS to the Cisco CVA122/CVA122E Cable Voice Adapter and back again.
Note
Exceeding this distance is a violation of the DOCSIS RFI specification.
When preparing a site for network connections to the Cisco CVA122/CVA122E Cable Voice Adapter, consider the following:
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The number of amplifiers from the installation site to the nearest node
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The number of outlets and amplifiers at the installation site
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Cable pinouts if you plan to build your cables
Potential distance limitation problems in the CATV network can be reduced by doing the following:
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A correct, linear unity gain two-way sweep procedure is in place
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Industry-standard configuration practices are used at the headend
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The downstream frequency is known at the time of installation
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The absolute downstream signal level can be measured where it enters the cable voice adapter
Required Tools and Equipment
Assemble the tools and equipment needed to install the Cisco CVA122/CVA122E Cable Voice Adapter at subscriber sites. Table 2-2 lists the recommended items that Cisco does not provide.
The Cisco CVA122/CVA122E Cable Voice Adapter is available in differing bulk box and single packages:
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Bulk box packages include: ten Cisco CVA122/CVA122E Cable Voice Adapters, ten support stands, ten power supplies, ten power cords based on the country of operation, one USB driver software installation CD, the release notes for the included version of Cisco IOS software, safety and warranty information, one copy of the Cisco CVA122/CVA122E Cable Voice Adapter User Guide, and ten copies of the Quick Start, Cisco CVA122/CVA122E Cable Voice Adapter Subscriber Setup card.
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Single packages include: one Cisco CVA122/CVA122E Cable Voice Adapter, one power supply, one support stand, one power cord appropriate for the country of operation, one 10BaseT Ethernet straight-through cable, one USB driver software installation CD, one copy of the Cisco CVA122/CVA122E Cable Voice Adapter User Guide, and one copy of the Quick Start, Cisco CVA122/CVA122E Cable Voice Adapter Subscriber Setup card.
CautionUse only the Cisco-provided power supply. Using any other vendor's power supply can cause loss of data or permanent damage. Ensure the power cord is suitable for your country of operation.
The subscriber in-box documentation set includes:
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Quick Start, Cisco CVA122/CVA122E Cable Voice Adapter Subscriber Setup card
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Cisco CVA122/CVA122E Cable Voice Adapter User Guide
The service provider in-box documentation set includes:
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Warranty card
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Licensing information
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Release notes for the shipping Cisco IOS Release image
The following additional documents are available via CCO:
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Cisco CVA122/CVA122E Cable Voice Adapter Hardware Installation Guide—this document
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Cisco CVA122 Cable Voice Adapter Features guide
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Cisco CVA122E Cable Voice Adapter Features guide
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Release notes are available for all Cisco IOS Release images
Based on the number of subscriber sites you are scheduled to install, ensure that you have sufficient Cisco-provided bulk box packages. After you have completed installation, give each subscriber a copy of the Quick Start, Cisco CVA122/CVA122E Cable Voice Adapter Subscriber Setup card, along with any documentation your company provides.
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