Dc Power Circuit Breaker Requirements For The Srx5800 Services Gateway; Dc Power Source Cabling For The Srx5800 Services Gateway - Juniper SRX5800 Hardware Manual

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DC Power Circuit Breaker Requirements for the SRX5800 Services Gateway

If you plan to operate a maximally configured DC-powered services gateway with standard-capacity power
supplies, we recommend that you provision at least 116 A (58 A per feed) @ –48 VDC (nominal) for the
system. Use a customer site circuit breaker rated according to respective National Electrical Code and
customer site internal standards to maintain proper level of protection for the current specified above.
If you plan to operate a maximally configured DC-powered services gateway with high-capacity power
supplies, we recommend that you provision at least 208 A (104 A per supply) @ –48 VDC (nominal) for
the system. This is maximum current draw at –48 VDC when two power supplies are providing the power
to the system and the redundant power supplies are not supplying power or not present. Use a customer
site circuit breaker rated according to respective National Electrical Code and customer site internal
standards to maintain proper level of protection for the current specified above.
If you plan to operate a DC-powered services gateway at less than the maximum configuration, we
recommend that you provision a circuit breaker according to respective National Electrical Code and
customer site internal standards to maintain proper level of protection for the current specified above or
each DC power supply rated for at least 125% of the continuous current that the system draws at –48
VDC.

DC Power Source Cabling for the SRX5800 Services Gateway

Figure 22 on page 65 shows a typical DC source cabling arrangement.
Figure 22: Typical DC Source Cabling to the Services Gateway
The DC power supplies in slots PEM0 and PEM1 must be powered by dedicated power feeds derived
from feed A, and the DC power supplies in slots PEM2 and PEM3 must be powered by dedicated power