Maintaining MX104 Power System Components
Replacing an MX104 AC Power Supply
Removing an MX104 AC Power Supply
Before you remove a power supply, be aware of the following:
The minimum number of power supplies must be present in the router at all times.
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.
After powering off a power supply, wait at least 60 seconds before turning it back on.
To remove an AC power supply (see Figure 2):
- Switch off the dedicated customer site circuit breaker for the power supply, and remove the power cord from the AC power source. Follow the instructions for your site.
- Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
- Swing the power cord retention clip out of the way of the power cord.
- Remove the power cord from the power supply.
- Press the release latch on the right side of the power supply to disconnect the power supply from the chassis.
- Pull the power supply straight out of the chassis.


See Also
Installing an MX104 AC Power Supply
See Also
Replacing an MX104 DC Power Supply
Removing an MX104 DC Power Supply
To remove a DC power supply from the router, you need the following tools:
Phillips (+) screwdriver, number 2
ESD grounding wrist strap
Before you remove a power supply, be aware of the following:
The minimum number of power supplies must be present in the router at all times.
Before you perform DC power procedures, ensure there is no power to 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 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.
After powering off a power supply, wait at least 60 seconds before turning it back on.
To remove a DC power supply (see Figure 6):
- Switch off the dedicated customer site circuit breaker for the power supply being removed. Follow your site's procedures for ESD.
- 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.
- Verify that the status LED on the power supply is not lit.
- Attach an ESD grounding strap to your bare wrist, and connect the other end of the strap to an ESD grounding point.
- Remove the clear plastic cover protecting the terminal studs on the faceplate (see Figure 4).
- Remove the screw and washer from each of the terminals. (Use a number 2 Phillips screwdriver.)
- Remove the cable lugs from the terminals.
- Carefully move the power cables out of the way.
- Remove the nut and washer from the DC power supply grounding point (see Figure 5).
- Remove the cable lug from the grounding point.
- Move the grounding cable out of the way.
- Press the release latch on the right side of the power supply to disconnect the power supply from the chassis.
- Grasp the handle on the power supply and pull the power supply straight out of the chassis.



See Also
Installing an MX104 DC Power Supply
Before you perform DC power procedures, ensure there is no power to 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 in the router, you need the following tools:
Phillips (+) screwdriver, number 2
ESD grounding wrist strap
Grounding ring lug with hole sized for an M5 screw
M5 nut and washer (one per DC power supply, attached)
DC power source cables, minimum 14 AWG or as required by local code (not provided)
DC power ring lugs, Panduit PV12-14HDRB-2k
M6 screws and washers (two per DC power supply, attached)
Grounding cable, minimum 14 AWG or as required by local code (not provided)
To install a DC power supply (see Figure 8):

