Each 120-A DC power supply has the following components:
•
Four removable input power trays, labeled 0 through 3, from left to right. The input
power trays are hot-removable and hot-insertable. Each input power tray weighs 1.6
lb (0.7 kg).
Each input power tray has one input, labeled RTN and –48 V, from left to right, and has
its own 125-A circuit breaker located on the PDU above the input power tray.
•
LEDs to monitor the status of the power supply—PDU OK, –48 V 120 A, and CB ON.
•
Twenty-one monitored electronic fuses for the fan trays, control boards, and FPCs.
NOTE: There are no mechanicalfuses in the PDUto be replaced.For output
voltage, current protectionis providedby electronic fuses, hot-swap circuits,
or ORing circuit. Electronic fuses and hot-swapcircuitsalso providecurrent
limitation.
NOTE: The PDUs contain no fans, but are cooled by the fans in the power
supply modules.
PTX5000 PDU Load Sharing
When the packet transport switch is operating normally and both PDUs are switched on,
load sharing between them occurs automatically. When one PDU fails or is turned off,
the other PDU immediately assumes the entire electrical load for the system. A single
PDU can provide full power for as long as the packet transport switch is operational.
PTX5000 DC Power Supply Module
PSM Slots
The PTX5000 Packet Transport Switch has eight PSMs, located in the lower front of the
chassis below the FPC card cage. The PSMs insert into one of four slots—labeled 0
through 3—located in the rear of each PDU labeled PDU0 and PDU1.
PSM Function
The power supply modules provide voltage regulation and filtering. Each PSM produces
the output voltages, which are distributed by the PDUs.
PSMs Supported
The packet transport switch supports the PSM in Table 17 on page 39.
Table 17: Supported Power Distribution Units
FirstSupportedJunos OS ReleaseModel NumberName
12.1x48PSM-PTX-DC-120DC PSM (120 A)
39Copyright © 2012, Juniper Networks, Inc.
Chapter 3: PTX5000 Hardware Components Overview
To Next Page
Loading...
