Installing an SRX5800 Services Gateway DC Power Supply
 | 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. |
To install a DC power supply (see Figure 1):
- 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.
- Attach an ESD grounding strap to your bare wrist,
and connect the strap to one of the ESD points on the chassis.
- Move the DC circuit breaker on the power supply
faceplate to the off (O) position.
- Ensure that the release lever below the empty power
supply slot is locked in the counterclockwise position (see Figure 1).
If necessary, pull the spring-loaded locking pin in the release
lever away from the chassis and turn the release lever counterclockwise
until it stops. Let go of the locking pin in the release lever. Ensure
that the pin is seated inside the corresponding hole in the chassis.
- Using both hands, slide the power supply straight
into the chassis until the power supply is fully seated in the chassis
slot. The power supply faceplate should be flush with any adjacent
power supply faceplates.
The small tab on the metal housing that is controlled by the
release lever must be inside of the corresponding slot at the bottom
of the power supply (see Figure 1). This tab is used to pull the power supply down in the chassis
slot, prior to removing the power supply.
Figure 1: Installing
a DC Power Supply
- While firmly pushing the handle on the power supply faceplate
with one hand, use your other hand to pull the spring-loaded locking
pin in the release lever away from the chassis and turn the release
lever clockwise until it stops.
- Let go of the locking pin in the release lever.
Ensure that the pin is seated inside the corresponding hole in the
chassis.
- Remove the clear plastic cover protecting the terminal
studs on the faceplate.
- Remove the nuts and washers from the terminal studs.
- Secure each power cable lug to the terminal studs,
first with the split washer, then with the nut. Apply between 23 lb-in.
(2.6 Nm) and 25 lb-in. (2.8 Nm) of torque to each nut
(see Figure 2).
- Attach the positive (+) DC source power cable lug to the RTN (return) terminal.
- Attach the negative (–) DC source power cable lug
to the –48V (input) terminal.
 | Caution:
You must ensure that power connections maintain the proper polarity.
The power source cables might be labeled (+) and (–) to indicate their polarity. There is no standard color coding for
DC power cables. The color coding used by the external DC power source
at your site determines the color coding for the leads on the power
cables that attach to the terminal studs on each power supply. |
 | Note:
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 PEM2 and PEM3 must be powered by dedicated power feeds derived from feed B. This configuration provides the commonly deployed A/B feed
redundancy for the system. |
Figure 2: Connecting DC Power
to the Services Gateway
- Loosen the captive screw on the cable restraint on the lower
edge of the power supply faceplate.
- Route the positive and negative DC power cables through
the left and right sides of the cable restraint.
- Tighten the cable restraint captive screw to hold
the power cables in place.
- Replace the clear plastic cover over the terminal
studs on the faceplate.
- Verify that the power cabling is correct, that
the cables are not touching, and that they do not block access to
services gateway components or drape where people could trip on them.
- Switch on the dedicated customer site circuit breaker.
- Verify that the INPUT OK LED on the
power suppply is lit steadily.
- Move the DC circuit breaker on the DC power supply
to the on (|) position .
- Verify that the BREAKER ON LED is
lit steadily.
- Verify that the PWR OK LED is lit
steadily.
Published: 2011-03-29