Specifications

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Cisco 7100 Series VPN Router Installation and Configuration Guide
78-6341-03
Chapter 2 Preparing for Installation
Safety Guidelines
Warning Never defeat the ground conductor or operate the equipment in the absence of a suitably installed
ground conductor. Contact the appropriate electrical inspection authority or an electrician if you are
uncertain that suitable grounding is available.
The Cisco 7100 series router installation must comply with all applicable codes and is approved for use
with copper conductors only. The ground bond fastening hardware should be of compatible material and
preclude loosening, deterioration, and electrochemical corrosion of hardware and joined material.
Attachment of the chassis ground to a central office or other interior ground system should be made with
a 6-AWG, copper ground conductor at a minimum.
The chassis employs two threaded chassis grounding receptacles, located on the sides near the rear of
the chassis, which are intended to be bonded directly to the central offices or other interior ground
system. The chassis ground requires M3.5 screws, which are included. (For instructions on how to
properly ground the chassis, see the “Attaching a System Ground Connection” section on page 3-4.)
• The AC-input power supply operates on input voltage and frequency within the ranges of 100 to 240
VRMS and 50/60 Hz without the need for operator adjustments. This power supply also incorporates
an active power factor corrector that minimizes the unwanted generation of line current harmonics
that can cause overload of site electrical distribution systems.
Note We recommend an uninterruptible power source to protect against power failures at your site. We
recommend powering a Cisco 7100 series router from a 15A receptacle at the power source.
Plant Wiring Guidelines
Following are guidelines for setting up the plant wiring and cabling at your site. When planning the
location of the new system, consider the distance limitations for signaling, EMC, and connector
compatibility, as described in the following sections.
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:
• Bad wiring practice can result in radio interference emanating from the plant wiring.
• Strong electromagnetic interference (EMI), especially when it is caused by lightning or radio
transmitters, can destroy the signal drivers and receivers in the router, and can even create an
electrical hazard by conducting power surges through lines and into equipment. (Review the safety
warnings in the “Electrical Equipment Guidelines” section on page 2-3.)
Note To predict and remedy strong EMI, you may also need to consult experts in radio frequency interference
(RFI).
If you use twisted-pair cable in your plant wiring with a good distribution of grounding conductors, the
plant wiring is unlikely to emit radio interference. If you exceed the recommended distances, use a
high-quality twisted-pair cable with one ground conductor for each data signal when applicable.