Cisco RFGW-10, Руководство по установке оборудования

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Cisco RF Gateway 10 Hardware Installation Guide
OL-16264-04
Chapter 2 Preparing Your Site for Installation
Site Planning
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 unshielded conductors to destroy
electronic devices. If you have had problems of this sort in the past, you may want to consult experts in
electrical surge suppression and shielding.
Asynchronous Terminal Connections
The Supervisor provides a console port to connect a terminal or computer for local console access. The
Supervisor also provides an auxiliary port to connect to a modem for remote dial-in console access.
Both ports have RJ-45 connectors, support RS-232 asynchronous data, and have distance
recommendations specified in the IEEE RS-232 standard.
Interference Considerations
When wires are run for any significant distance, there is a risk that stray signals will be induced on the
wires as interference. If interference signals are strong, they can cause data errors or damage to the
equipment.
The following sections describe sources of interference and how to minimize its effects on the
Cisco RFGW-10 UEQAM system.
Electromagnetic Interference
All equipment powered by AC current can propagate electrical energy that can cause electromagnetic
interference (EMI) and possibly affect the operation of other equipment. The typical sources of EMI are
equipment power cords and power service cables from electric utility companies.
Strong EMI can destroy the signal drivers and receivers in the Cisco RFGW-10 UEQAM and even create
an electrical hazard by causing power surges through power lines into installed equipment. These
problems are rare, but could be catastrophic.
To resolve these problems, you need specialized knowledge and equipment, which could consume
substantial time and money. However, you should ensure that you have a properly grounded and shielded
electrical environment, paying special attention to the need for electrical surge suppression.
Table 2-6 lists electrode magnetic compliance standards for the Cisco RFGW-10 UEQAM.
Table 2-6 EMC Standards
EMC Standards FCC 47 CFR Part 15 Class A
VCCI Class A
AS/NSZ Class A
ICES-003 Class A
EN55022/CISPR 22 Information Technology Equipment (Emissions)
EN55024/CISPR 24 Information Technology Equipment (Immunity)
EN300 386 Telecommunications Network Equipment (EMC)
EN50082-1/EN61000-6-1 Generic Immunity Standard
CE marking UL60950-1
CSA C22.2 No. 60950-1-03