3Com Router 5000 Family
Installation Guide
Chapter 3 Installation Preparation
3Com Corporation
3-3
The interference sources, no matter where they come from, affect the routers with
capacitance coupling, inductance coupling, radiation of electromagnetic wave,
common impedance (including the grounding system) or conducting line (power line,
signal line and transmission line etc.).
So the following should be considered:
z
Take effective measures to prevent the power system from being interfered with
by the power grid system.
z
Keep the router far away from the radio launcher, radar launcher, and
high-frequency devices working in high current.
z
Use electromagnetic shielding when necessary.
3.1.5 Requirements on Preventing Lightning
Although many measures have been taken to protect 3Com 5000 Routers from
lightning, if the lightning intensity exceeds a certain range, damage to the router may
still happen. To protect the router from lightning better, the following should be
considered:
z
Ensure the PGND wire of the chassis is well grounded.
z
Ensure the ground point of the socket of AC power supply is well grounded.
z
To enhance the lightning protection capability of the power supply, a lightning
arrester could be installed at the input end of the power supply.
z
As for the signal line outdoors to which the interface modules of 3Com 5000
Routers are connected, such as ISDN line, telephone line, E1/T1 line, etc, a
special lightning arrester should be installed at the input end of the signal line to
enhance the lightning protection capability.
3.1.6 Requirements on Workbench
No matter whether you are to install the router in the cabinet or directly place it on the
workbench, it is necessary to ensure that:
z
There is spacing reserved at the air inlet and outlet in the router so as to facilitate
the radiation of the router cabinet.
z
The cabinet and workbench have good radiation systems.
z
The cabinet and workbench are firm enough to support the router and other
installation accessories.
z
The cabinet and workbench are well grounded.
3.2 Precautions
Routers play a key role in data communications network. Please pay attention to the
following:
