Juniper QFX Series User Manual

DC Power Electrical Safety Guidelines
This topic applies to hardware devices in the EX Series product family, which includes
switches and the XRE200 External Routing Engine.
This topic also applies to hardware devices in the QFX Series.
•
A DC-powered device is equipped with a DC terminal block that is rated for the power
requirements of a maximally configured device.
NOTE: Tosupplysufficient power, terminate the DC input wiring on a facility
DC source that is capable of supplying:
•
Minimum of 7.5 A at –48 VDC for EX2200 and EX3300 switches
•
Minimum of 8 A at –48 VDC for EX3200 and EX4200 switches
•
Minimum of 50 A at –48 VDC for EX6210 switches
•
Minimum of 60 A at –48 VDC for EX8208 switches
•
Minimum of 100 A at –48 VDC for EX8216 switches
•
Minimum of 7 A at –48 VDC for QFX3500 devices
Incorporate an easily accessible disconnect device into the facility wiring. Be sure to
connect the ground wire or conduit to a solid office earth ground. A closed loop ring is
recommended for terminating the ground conductor at the ground stud.
•
Run two wires from the circuit breaker box to a source of 48 VDC.
•
A DC-powered device that is equipped with a DC terminal block is intended only for
installation in a restricted access location. In the United States, a restricted access
area is one in accordance with Articles 110-16, 110-17, and 110-18 of the National Electrical
Code ANSI/NFPA 70.
NOTE: Primary overcurrent protection is provided by the building circuit
breaker. This breaker must protect against excess currents, short circuits,
and earth grounding faults in accordance with NEC ANSI/NFPA 70.
•
Ensure that the polarity of the DC input wiring is correct. Under certain conditions,
connections with reversed polarity might trip the primary circuit breaker or damage
the equipment.
•
For personal safety, connect the green and yellow wire to safety (earth) ground at both
the device and the supply side of the DC wiring.
197Copyright © 2012, Juniper Networks, Inc.
Chapter 16: Power and Electrical Safety Information

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)