Juniper PTX5000 Hardware Manual page 110

Each 120-A DC PDU 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 120-A input power tray weighs 1.6 lb (0.7 kg), not including cables. The 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:
120-A DC PDU—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 mechanical fuses in the PDU to be replaced. For output voltage, current
protection is provided by electronic fuses, hot-swap circuits, or ORing circuit. Electronic fuses
and hot-swap circuits also provide current limitation.
NOTE: The PDUs contain no fans, but are cooled by the fans in the power supply modules.
High Capacity DC PDU Description
The High Capacity DC PDU (60-A) provides 30.4 kW power output and you can connect a maximum of
eight High Capacity PSMs to the PDU. Each DC PDU can receive up to sixteen 60-A DC input feeds
from source outputs and provides two isolated outputs, a 12 V output at 2034 A maximum and a 36-V
output at 167 A maximum. The 36-V output provides power to the vertical and horizontal fan trays and
the 12-V output provides power to the system boards such as FPCs, SIBs, Routing Engines, and Control
Boards (CBs). Additionally, the PSMs provide 5-V bias output to the PDUs. Each DC PDU can receive up
to sixteen 60-A DC input feeds and weighs 64.5 lb (29.3 kg).
NOTE: You cannot mix existing PDUs with the High Capacity DC PDU.
The following is a list of some of the features of the High Capacity DC PDU :
• Supports up to eight PSMs, each PSM requires two 60-A feeds.
• Operates from 40 VDC through 72 VDC.
• I2C bus protocol fault reporting and control.
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