Site Electrical Wiring Guidelines; Rack Requirements; Table 59: Site Electrical Wiring Guidelines - Juniper EX4300 Hardware Manual

Site Electrical Wiring Guidelines

Table 59: Site Electrical Wiring Guidelines

Site Wiring Factor
Signaling limitations
Radio frequency
interference
Electromagnetic
compatibility
Related
Documentation

Rack Requirements

Copyright © 2017, Juniper Networks, Inc.
Table 59 on page 93 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.
Guidelines
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.
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.
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 device
Electrical hazards as a result of power surges conducted over the lines into the equipment
General Safety Guidelines and Warnings on page 283
General Electrical Safety Guidelines and Warnings on page 311
Prevention of Electrostatic Discharge Damage on page 313
You can mount the device on two-post racks or four-post racks.
Rack requirements consist of:
Rack type
Mounting bracket hole spacing
Chapter 6: Preparation Overview
93