Juniper SRX4100, Руководство по оборудованию

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Site Electrical Wiring Guidelines
Table 13 on page 21 describes the factors you must consider while planning the electrical
wiring at your site.
CAUTION: It is particularly important to provide a properly grounded and
shielded environment and to use electrical surge-suppression devices.
Table 13: Site Electrical Wiring Guidelines
Guideline Site Wiring Factor
To ensure that signaling functions optimally:
• Install wires correctly.
Improperly installed wires can emit radio interference.
• Do not exceed the recommended distances or pass wires between
buildings.
The potential for damage from lightning strikes increases if wires exceed
recommended distances or if wires pass between buildings.
• Shield all conductors.
The electromagnetic pulse (EMP) caused by lightning can damage
unshielded conductors and destroy electronic devices.
Signaling limitations
To reduce or eliminate the emission of RFI from your site wiring:
• Use twisted-pair cable with a good distribution of grounding conductors.
• Use a high-quality twisted-pair cable with one ground conductor for
each data signal when applicable, if you must exceed the recommended
distances.
Radio frequency
interference (RFI)
Provide a properly grounded and shielded environment and use electrical
surge-suppression devices.
Strong sources of electromagnetic interference (EMI) can cause the
following damage:
•
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.
TIP: If your site is susceptible to problems with EMC, particularly from
lightning or radio transmitters, you might want to seek expert advice.
Electromagnetic
compatibility (EMC)
WARNING: Some ports are designed for use as intrabuilding interfaces only
Type 2 or Type 4 ports, the battery return connection is to be treated as an
Isolated DC return (that is, DC-I), as defined in GR-1089-CORE and require
isolation from the exposed OSP cabling. To comply with NEBS requirements
and protect against lightning surges and commercial power disturbances,
the intrabuilding port(s) of the device MUST NOT be metallically connected
21 Copyright © 2017, Juniper Networks, Inc.
Chapter 5: Planning and Preparing the Site