Juniper Networks EX4200 - Manual (Page 267)

Related Topics General Safety Guidelines and Warnings for EX Series Switches on page 207 ■
■ General Electrical Safety Guidelines and Warnings for EX Series Switches on
page 235
■ AC Power Electrical Safety Guidelines for EX Series Switches on page 238
DC Power Electrical Safety Guidelines for EX Series Switches
The following electrical safety guidelines apply to a DC-powered switch:
■ A DC-powered switch is equipped with a DC terminal block that is rated for the
power requirements of a maximally configured switch.
NOTE: To supply sufficient power, terminate the DC input wiring on a facility DC
source capable of supplying at least 8 A at –48 VDC for EX3200 and EX4200 switches.
To supply sufficient power, terminate the DC input wiring on a facility DC source
capable of supplying at least 60 A at –48 VDC for EX8208 switches.
To supply sufficient power, terminate the DC input wiring on a facility DC source
capable of supplying at least 100 A at –48 VDC for EX8216 switches.
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 router 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.
DC Power Electrical Safety Guidelines for EX Series Switches ■ 241
Chapter 20: Power and Electrical Safety Information