Table Of Contents
Location and Mounting Requirements
Temperature Control and Ventilation
Distance Limitations for Interface Cables
Fast Ethernet Maximum Distance
FXS Analog Voice Port Maximum Distance
Planning Your Installation
Before you install your Cisco VG202 and Cisco VG204 voice gateways, consider the information in this chapter:
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Location and Mounting Requirements
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Location and Mounting Requirements
There are two ways of mounting the Cisco VG202 and Cisco VG204 voice gateways:
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Whether wall or desktop, the mounting location must provide the following:
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Temperature Control and Ventilation
The installation area (room, closet, or cabinet) for the Cisco VG202 and Cisco VG204 voice gateways should always be well ventilated and should provide adequate air circulation to ensure proper cooling. The room temperature should be maintained from 32 to 122°F (0 to 50°C).
Wall Mounting
If the Cisco VG202 and Cisco VG204 voice gateways are installed on a wall, there should be plenty of space on both sides to ensure that there is adequate airflow through the chassis.
Desktop Mounting
If the voice gateway is placed on a desktop, do not stack other equipment or paper on the chassis. Provide plenty of space for air circulation at all four sides of the gateway. Inadequate ventilation can result in overheating and damage.
Access to Chassis
Allow space at the back of the chassis for cable connections. Also consider the need to access the chassis for future upgrades, maintenance, and troubleshooting.
Power Source
Warning
Warning
Warning
Warning
Cable Types
For information on cable types, see the white papers associated with this product.
Distance Limitations for Interface Cables
When planning your installation, consider distance limitations and potential electromagnetic interference (EMI) as defined by the Electronic Industries Association (EIA). Distance limitation information is included for the following voice gateway ports:
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Fast Ethernet Maximum Distance
The maximum segment distance for Fast Ethernet is 330 feet (100 meters) (specified in IEEE 802.3).
FXS Analog Voice Port Maximum Distance
The maximum distance is established by a total allowable loop resistance, including the phone or terminal equipment, of 600 ohm.
Interference Considerations
When you run cables for any significant distance in an electromagnetic field, interference can occur between the electromagnetic field and the signals on the cables. This has two implications for the installation of terminal plant cabling:
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If you use twisted-pair cables with a good distribution of grounding conductors in your plant cabling, then emitted radio interference is unlikely.
If your cables exceed the recommended distances, or if your cables pass between buildings, you must give special consideration to the effect of lightning strikes or ground loops. If your site has these characteristics, consult experts in lightning suppression and shielding. The electromagnetic pulse caused by lightning or other high-energy phenomena can easily couple enough energy into unshielded conductors to destroy electronic devices.
Most data centers cannot resolve the infrequent but potentially catastrophic problems of EMI without using pulse meters and other special equipment. Take precautions to avoid these problems by providing a properly grounded and shielded environment and by installing electrical surge suppression.
If you remove any module, you must either install a module in its place or install a cover plate over the opening. To prevent electromagnetic interference, all module openings must be either occupied or covered.
For advice on the prevention of electromagnetic interference, consult experts in radio-frequency interference (RFI).
