Juniper SRX 5800, Hardware Manual

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Connecting Power to a DC-Powered SRX5800 Services Gateway
WARNING: Before performing DC power procedures, ensure that power is removed
from the DC circuit. To ensure that all power is off, locate the circuit breaker on the
panel board that services the DC circuit, switch the circuit breaker to the off position,
and tape the switch handle of the circuit breaker in the off position.
WARNING: To meet safety and electromagnetic interference (EMI) requirements and
to ensure proper operation, you must properly ground the services gateway chassis
before connecting power. See “Grounding the SRX5800 Services Gateway” on page 239
for instructions.
CAUTION: Do not mix AC and DC power supplies within the same services gateway.
Damage to the services gateway might occur.
You connect DC power to the services gateway by attaching power cables from the external DC power
sources to the terminal studs on the power supply faceplates. You must provide the power cables (the
cable lugs are supplied with the services gateway).
To connect the DC source power cables to the services gateway:
1. Switch off the dedicated customer site circuit breakers. Ensure that the voltage across the DC power
source cable leads is 0 V and that there is no chance that the cable leads might become active during
installation.
2. Attach an ESD grounding strap to your bare wrist, and connect the strap to one of the ESD points on
the chassis.
3. Move the DC circuit breaker on the power supply faceplate to the off (O) position.
4. Remove the clear plastic cover protecting the terminal studs on the faceplate.
5. Verify that the DC power cables are correctly labeled before making connections to the power supply.
In a typical power distribution scheme where the return is connected to chassis ground at the battery
plant, you can use a multimeter to verify the resistance of the –48V and RTN DC cables to chassis
ground:
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