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This chapter recommends general safety guidelines to follow and identifies requirements to meet before going to a subscriber site to install a Cisco uBR924 cable access router. It also lists the major Federal Communications Commission (FCC), Underwriter Laboratory (UL), and other agency approvals for the router. For additional safety and regulatory information, see "Regulatory Compliance and Safety Information."
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Warning Only trained and qualified personnel should be allowed to install or replace this equipment. |
The chapter includes the following sections:
This section describes the general, electrical, and electrostatic discharge guidelines that should be followed when installing the Cisco uBR924 cable access router.
Follow these guidelines to ensure general safety:
Follow these guidelines when working with electrical equipment:
In addition, follow these guidelines when working with equipment that is disconnected from a power source, but still connected to cable wiring.
Electrostatic discharge (ESD) damage, which occurs when electronic cards or components are improperly handled, can result in complete or intermittent system failures. The Cisco uBR924 cable access router consists of a printed circuit board that is housed in a metal 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 uBR924 cable access router. 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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Caution For safety, periodically check the resistance value of the antistatic strap. The measurement should be between 1 and 10 megohm (Mohm). |
Before going to a subscriber site to install the Cisco uBR924 cable access router, verify that the following have been done:
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Note Cisco recommends that a dedicated (new) CATV cable drop be run from the grounding block directly to the Cisco uBR924 cable access router. 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. For the United States, refer to the National Electrical Code Section 820-40 guidelines for proper grounding. |
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Note Installing a high pass filter between the Cisco uBR924 router and the headend will prevent the router from connecting to the headend---in this situation, the router's US LED will never light. |
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Note This recommendation is for Internet access in general and is not specific to the Cisco uBR924. Other operating systems and hardware platforms of comparable capability are also supported. |
Table 2-1 lists the operating and nonoperating environmental site requirements for operation of the Cisco uBR924 router. The ranges indicate the minimum and maximum values allowed for the router'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.
| Specification | Minimum | Maximum |
|---|---|---|
Temperature, ambient operating | 32° F (0° C) | 104° F (40° C) |
Temperature, ambient nonoperating and storage | -13° F (-25° C) | 95° F (70° C) |
Humidity, ambient (noncondensing) operating | 5% | 95% |
Humidity, ambient (noncondensing) nonoperating and storage | 5% | 95% |
Altitude, operating and nonoperating | Sea level | 10,000 ft (3,050 m) |
Vibration, operating | 10 to 200 Hz, 0.0005 g (1 oct./min.) | N/A |
Vibration, nonoperating | 10 to 100 Hz, 0.0065 g (1 oct./min.) | N/A |
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Caution For proper airflow, keep the back, sides, and bottom of the cable access router clear of obstructions and away from the exhaust of other equipment. To prevent unit overheating, never install the Cisco uBR924 router in an enclosed rack or room that is not properly ventilated or air conditioned. |
The Cisco uBR924 router does not contain a power switch. After the cable system technician installs, connects, powers on, and initializes the unit, it is intended to remain connected to the broadband network when operating normally. Before plugging the unit in, verify that the power source is within the values given in Table 2-2.
| Description | Specification |
|---|---|
AC-input voltage | 120 to 240 VAC1 wide input with power factor correction |
AC-input current rating | 1.2A2 maximum at 120 VAC and 0.6A maximum at 240 VAC |
AC-input cable | 18 AWG3 three-wire cable, with a three-lead receptacle on the power supply end, and a North American (NEMA 5-15P) plug on the power source end; other country-specific cords are available and supplied as ordered. |
Power dissipation | 12 to 15W |
Frequency | 50/60 Hz4 |
| 1VAC = volts alternating current. 2A = ampere. 3AWG = American Wire Gauge. 4Hz = hertz. |
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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. |
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.
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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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.
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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 Cisco uBR924 router user. |
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.
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Note The center conductor should extend 1/8 inch (3.2 mm) beyond the end of the conductor. |
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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. |
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Note Exceeding this distance is a violation of the DOCSIS RFI specification. |
When preparing a site for network connections to the Cisco uBR924 router, consider the following:
Potential distance limitation problems in the CATV network can be reduced by ensuring the following factors:
The Cisco uBR924 router interfaces with national cable, telco, and network installations, which are subject to government regulation and oversight. Please read the following sections to verify that the installation of the router is within the parameters imposed by the regulatory bodies that are responsible for the subscriber's site. Additional information is available in "Regulatory Compliance and Safety Information."
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
The FCC has established rules that permit the device to be directly connected to the telephone network. Standardized jacks are used for these connections. This equipment should not be used on party lines or coin phones.
If this device is malfunctioning, it may also be causing harm to the telephone network; this device should be disconnected until the source of the problem can be determined and until repair has been made. If this is not done, the telephone company may temporarily disconnect service.
The telephone company may make changes in its technical operations and procedures; if such changes affect the compatibility or use of this device, the telephone company is required to give adequate notice of the changes. You will be advised of your rights to file a complaint with the FCC.
If the telephone company requests information on what equipment is connected to their lines, inform them of:
The ringer equivalence number (REN) and the FCC registration number are indicated on the label. The ringer equivalence number determines the maximum devices that can be connected to your telephone line. In most areas, the sum of the RENs of all devices on any one line should not exceed five. If too many devices are attached, they may not ring properly.
As of the date of the publication of this manual, the Cisco uBR924 router is approved to operate in the following countries:
Other companies might have been added to this list since the date of publication. See the release notes for this product for any additions.
This product is UL-listed, CSA-approved, and TUV-certified for the uses described in this guide.
NOTICE: This product is Canadian Industry certified. The Industry Canada Certification Number is 2461 9904 A. This certification means that the equipment meets certain telecommunications network protective, operational and safety requirements. The Department does not guarantee the equipment will operate to the user's satisfaction.
Before installing this equipment, users should ensure that it is permissible to be connected to the facilities of the local telecommunications company. The equipment must also be installed using an acceptable method of connection. In some cases, the company's inside wiring associated with a single line individual service may be extended by means of a certified connector assembly (telephone extension cord). The customer should be aware that compliance with the above conditions may not prevent degradation of service in some situations.
Repairs to the certified equipment should be made by an authorized Canadian maintenance facility designated by the supplier. Any repairs or alterations made by the user to this equipment, or equipment malfunctions, may give the telecommunications company cause to request the user to disconnect the equipment.
Users should ensure for their own protection that the electrical ground connections of the power utility, telephone lines and internal metallic water pipe system, if present, are connected together. This precaution may be particularly important in rural areas.
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Caution Users should not attempt to make such connections themselves, but should contact the appropriate electric inspection authority, or electrician, as appropriate. |
The Ringer Equivalence Number (REN) assigned to each terminal device denotes the percentage of the total load to be connected to a telephone loop which is used by the device, to prevent overloading. The termination on a loop may consist of any combination of devices subject only to the requirement that the total REN of all the devices does not exceed five.
Assemble the tools and equipment needed to install the Cisco uBR924 router at subscriber sites. Table 2-3 lists the recommended items that Cisco does not provide.
| Checked Off | Item |
|---|---|
| Installation toolkit including a flathead screwdriver (small to medium size); Phillips screwdriver (small to medium size); 7/16-inch open-end wrench; ESD-preventive wrist strap |
| Signal level meter capable of reading a 64 QAM signal or a spectrum analyzer (HP8594Q or equivalent) as appropriate. An alternative is a clear understanding of the digital-to-analog channel amplitude offset and a calibrated analog signal level meter to measure a nearby adjacent analog carrier. |
| Mixed set of attenuators (pads), cable adapters, splitters, High Pass Filters (HPF), directional couplers as appropriate |
| Telephone tester (handset) to check the backup POTS telephone line (optional) |
| 10BaseT Ethernet cable tester |
| Portable, hand-held console terminal such as a laptop computer with RS-232 serial port communications software, and a setting of 9600 baud, 8 data bits, no parity, and 1 stop bit (9600 8N1); reserved for technicians in networks supporting remote configuration and troubleshooting. |
| Connector assemblies/adapters and wiring items for subscriber sites that support multiple telephones or fax devices on a VoIP telephone line; items and wiring must be in accordance with regulations in the country of operation. |
| Applicable cables based on the subscriber site configuration:
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The Cisco uBR924 cable access router is available in differing bulk box and single packages:
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Caution Use only the Cisco-provided power supply and cord. Using any other vendor's power supply and cord can cause loss of data or permanent damage. Ensure the power cord is suitable for your country of operation. Cisco uBR904 and Cisco uBR924 power supplies and cords are identical and interchangeable, provided the power cords are applicable to the country of operation. |
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Note A cable console kit and console cable, used to locally reconfigure the router, can be purchased separately. |
The subscriber in-box documentation set includes:
The service provider in-box documentation set includes:
The following additional documents are available via CCO:
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 uBR924 Cable Access Router Subscriber Setup publication, along with any documentation your company provides.
Posted: Fri Mar 24 10:18:06 PST 2000
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