Juniper QFX Series User Manual

WARNING: It is particularly important to provide a properly grounded and
shielded environment and to use electrical surge-suppression devices.
Table 19: Site Electrical Wiring Guidelines
GuidelinesSite 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 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 on page 161•
• General Electrical Safety Guidelines and Warnings on page 191
• Prevention of Electrostatic Discharge Damage on page 192
• Power Supply in EX2200 Switches
• Power Supply in EX3200 Switches
• Power Supply in EX3300 Switches
• Power Supply in EX4200 Switches
• AC Power Supply in EX4500 Switches
• DC Power Supply in EX4500 Switches
• AC Power Supplies in an EX6200 Switch
• DC Power Supply in an EX6200 Switch
• AC Power Supply in an EX8200 Switch
• DC Power Supply in an EX8200 Switch
• AC Power Supply in a QFX3100 Director Device on page 30
Copyright © 2012, Juniper Networks, Inc.88
QFX3000 Hardware Documentation

Juniper QFX Series Specifications

General

Category	Switch
Series	QFX
Form Factor	1U, 2U, and modular chassis options
Power Supply	Redundant, hot-swappable power supplies
Cooling	hot-swappable fans
Virtual Chassis	Supported on certain models
Typical Use	Data center, cloud
Operating System	Junos OS
Management	CLI
Key Features	High performance, low latency, automation
Latency	Sub-microsecond latency
Port Density	Varies by model (e.g., QFX5100: up to 48x10GbE + 6x40GbE)