Replacing an SRX5800 Services Gateway DC Power Supply

To replace a DC power supply, perform the following procedures:

1. Removing an SRX5800 Services Gateway DC Power Supply
2. Installing an SRX5800 Services Gateway DC Power Supply

Removing an SRX5800 Services Gateway DC Power Supply

Before you remove a power supply, be aware of the following:

Note: The minimum number of power supplies must be present in the services gateway at all times.

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.

Caution: To maintain proper cooling and prevent thermal shutdown of the operating power supply unit, each power supply slot must contain either a power supply or a blank panel. If you remove a power supply, you must install a replacement power supply or a blank panel shortly after the removal.

Note: After powering off a power supply, wait at least 60 seconds before turning it back on.

To remove a DC power supply (see Figure 1):

1. Switch off the dedicated customer site circuit breaker for the power supply being removed. Follow your site's procedures for ESD.
2. Make sure that the voltage across the DC power source cable leads is 0 V and that there is no chance that the cables might become active during the removal process.
3. Verify that the INPUT OK LEDs on the power supply to be removed are not lit.
4. Attach an ESD grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
5. Move the DC circuit breaker on the power supply faceplate to the off (O) position.
6. Remove the clear plastic cover protecting the terminal studs on the faceplate.
7. Remove the nuts and washers from the terminal studs. (Use a 7/16-in. nut driver or socket wrench.)
8. Remove the cable lugs from the terminal studs.
9. Loosen the captive screw on the cable restraint on the lower edge of the power supply faceplate.
10. Carefully move the power cables out of the way.
11. While grasping 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 counterclockwise until it stops.
12. Let go of the locking pin in the release lever. Ensure that the pin is seated inside the corresponding hole in the chassis.
13. Pull the power supply straight out of the chassis. The power supply can weigh up to 5 lb (2.3 kg). Be prepared to accept its full weight.

    Figure 1: Removing a DC Power Supply from the Services Gateway

    

    Warning: Do not touch the power connector on the top of the power supply (see Figure 2). It can contain dangerous voltages.

    Figure 2: Top of the Power Supply Showing Midplane Connector

    

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 3):

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.
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. Ensure that the release lever below the empty power supply slot is locked in the counterclockwise position (see Figure 3).

   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.

5. 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 3). This tab is used to pull the power supply down in the chassis slot, prior to removing the power supply.

   Figure 3: Installing a DC Power Supply

   
6. 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.
7. Let go of the locking pin in the release lever. Ensure that the pin is seated inside the corresponding hole in the chassis.
8. Remove the clear plastic cover protecting the terminal studs on the faceplate.
9. Remove the nuts and washers from the terminal studs.
10. 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 4).
    1. Attach the positive (+) DC source power cable lug to the RTN (return) terminal.
    2. 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 4: Connecting DC Power to the Services Gateway

    
11. Loosen the captive screw on the cable restraint on the lower edge of the power supply faceplate.
12. Route the positive and negative DC power cables through the left and right sides of the cable restraint.
13. Tighten the cable restraint captive screw to hold the power cables in place.
14. Replace the clear plastic cover over the terminal studs on the faceplate.
15. 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.
16. Switch on the dedicated customer site circuit breaker.
17. Verify that the INPUT OK LED on the power suppply is lit steadily.
18. Move the DC circuit breaker on the DC power supply to the on (|) position .
19. Verify that the BREAKER ON LED is lit steadily.
20. Verify that the PWR OK LED is lit steadily.