Juniper EX4300, Руководство по оборудованию

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Site Electrical Wiring Guidelines
This topic applies to hardware devices in the EX Series product family, which includes
EX Series switches, the EX Series Redundant Power System (RPS), and the XRE200
External Routing Engine.
This topic also applies to hardware devices in the QFX Series and to OCX1100 switches.
Table 58 on page 89 describes the factors you must consider while planning the electrical
wiring at your site.
WARNING: It is particularly important to provide a properly grounded and
shielded environment and to use electrical surge-suppression devices.
Table 58: Site Electrical Wiring Guidelines
Guidelines Site Wiring Factor
If your site experiences any of the following problems, consult experts in
electrical surge suppression and shielding:
• Improperly installed wires cause radio frequency interference (RFI).
• Damage from lightning strikes occurs when wires exceed recommended
distances or pass between buildings.
• Electromagnetic pulses (EMPs) caused by lightning damage unshielded
conductors and electronic devices.
Signaling limitations
To reduce or eliminate RFI from your site wiring, do the following:
• Use a 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 on page 265
•
•
General Electrical Safety Guidelines and Warnings on page 297
•
Prevention of Electrostatic Discharge Damage on page 299
•
Power Supply in EX2200 Switches
89 Copyright © 2015, Juniper Networks, Inc.
Chapter 6: Preparation Overview