Dell PowerConnect J-EX4200, Hardware Manual

Page: 76 / 238

Table 24: Site Electrical Wiring Guidelines (continued)
Guidelines Site Wiring Factor
To reduce or eliminate radio frequency interference (RFI) from
your site wiring, do the following:
• Use twisted-pair cable with a good distribution of grounding
conductors.
• If you must exceed the recommended distances, use a
high-quality twisted-pair cable with one ground conductor
for each data signal when applicable.
Radio frequency interference
If your site is susceptible to problems with electromagnetic
compatibility (EMC), particularly from lightning or radio
transmitters, seek expert advice.
Some of the problems caused by strong sources of
electromagnetic interference (EMI) are:
• Destruction of the signal drivers and receivers in the switch
•
Electrical hazards as a result of power surges conducted
over the lines into the equipment
Electromagnetic compatibility
Related
Documentation
General Safety Guidelines and Warnings for J-EX Series Switches on page 171
•
•
General Electrical Safety Guidelines and Warnings for J-EX Series Switches on page 197
•
Prevention of Electrostatic Discharge Damage on J-EX Series Switches on page 198
•
Power Supply in J-EX4200 Switches on page 21
Environmental Requirements and Specifications for J-EX Series Switches
The switch must be installed in a rack or cabinet housed in a dry, clean, well-ventilated,
and temperature-controlled environment.
Ensure that these environmental guidelines are followed:
• The site must be as dust-free as possible, because dust can clog air intake vents and
filters, reducing the efficiency of the switch cooling system.
•
Maintain ambient airflow for normal switch operation. If the airflow is blocked or
restricted, or if the intake air is too warm, the switch might overheat, leading to the
switch temperature monitor shutting down the switch to protect the hardware
components.
Table 25 on page 60 provides the required environmental conditions for normal switch
operation.
Table 25: J-EX Series Switch Environmental Tolerances
Tolerance Description
No performance degradation to 10,000 feet (3048 meters) Altitude
60
Dell PowerConnect J-Series J-EX4200 Ethernet Switch Hardware Guide