Cisco VG202/VG202XM and Cisco VG204/VG204XM Voice Gateways Hardware Installation Guide
Planning Your Installation
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Planning Your Installation

Table Of Contents

Planning Your Installation

Location and Mounting Requirements

About Mounting Location Requirements

Access to the Chassis

Power Source

Temperature Control and Ventilation

Temperature Control

Ventilation for Wall Mounting

Ventilation for Desktop Mounting

Distance Limitations for Interface Cables

Fast Ethernet Maximum Distance

FXS Analog Voice Port Maximum Distance

Interference Considerations


Planning Your Installation


Location and Mounting Requirements

Distance Limitations for Interface Cables

Location and Mounting Requirements

About Mounting Location Requirements

Access to the Chassis

Power Source

Temperature Control and Ventilation

About Mounting Location Requirements

You can mount a Cisco VG202, Cisco VG202XM, Cisco VG204, or Cisco VG204XM voice gateway chassis onto either a wall or on a desk or shelf.

The mounting location must provide the following:

Adequate access to the chassis. See Access to the Chassis.

Access to a suitable power source. See Power Source.

Allowance for adequate heat dissipation and airflow around the chassis. Inadequate ventilation can result in overheating and damage. See Temperature Control and Ventilation.

Access to an appropriate earth ground. See Installing the Ground Connection.

Access to the 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 Do not work on the system or connect or disconnect cables during periods of lightning activity. Statement 1001

Warning Read the installation instructions before you connect the system to its power source. Statement 1004

Warning This product relies on the building's installation for short-circuit (overcurrent) protection. Ensure that the protective device is rated not greater than:120 VAC, 15A U.S. (240 VAC, 10A international) Statement 1005

Warning The device is designed for connection to TN and IT power systems. Statement 1007

Temperature Control and Ventilation

Temperature Control

Ventilation for Wall Mounting

Ventilation for Desktop Mounting

Temperature Control

The installation area (room, closet, or cabinet) for the voice gateway chassis must be well ventilated and provide adequate air circulation to ensure proper cooling. The room temperature should be maintained between 32 to 122 degrees F (0 to 50 degrees C).

Ventilation for Wall Mounting

If you install the chassis onto a wall, ensure that there is plenty of space on all sides of the chassis to allow adequate airflow through the chassis.

Ventilation for Desktop Mounting

If you place the chassis on a desk or shelf, do not stack other equipment or paper on top of it. Provide plenty of space for air circulation on all four sides of the chassis.

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).

Fast Ethernet Maximum Distance

FXS Analog Voice Port Maximum Distance

Interference Considerations

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:

Unshielded plant cabling can emit radio interference.

Strong electromagnetic interference (EMI), especially caused by lightning or radio transmitters, can destroy the EIA/TIA-232 drivers and receivers in the Cisco VG202, Cisco VG202XM, Cisco VG204, or Cisco VG204XM voice gateways.

If you use twisted-pair cables with a good distribution of grounding conductors in your plant cabling, 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).