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.
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD 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
To install an AC power supply (see Figure 3):
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD point.
- 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 faceplate or blank installed in the power supply slot.
- Attach the power cord to the power supply.
- Secure the power cord with the power cord retainer clip.
- Attach the power cord to the AC power source, and switch
on the dedicated customer site circuit breaker. Follow the instructions
for your site.
Observe the status LED on the power supply faceplate. If the power supply is correctly installed and functioning normally, the status LED lights green steadily.
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 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 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.
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD 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 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 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):
- 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.
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD point.
- 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 faceplate or blank installed in the power supply slot.
- Remove the clear plastic cover protecting the terminal on the faceplate.
- Ground the DC power supply (see Figure 7):
Remove the nut and washer from the grounding point on the power supply.
Secure each grounding cable lug to the grounding point with the washer and nut.
Figure 7: Connecting a DC Power Supply Grounding Cable - Remove the screws and washers from the DC terminals.
- 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 DC cables to chassis ground:
For –48V and –60V:
The cable with very high resistance (indicating an open circuit) to chassis ground is the DC input cable (
–).The cable with very low resistance (indicating a closed circuit) to chassis ground is the return cable (
+).
For +24V:
The cable with very low resistance (indicating a closed circuit) to chassis ground is the DC input cable (
–).The cable with very high resistance (indicating an open circuit) to chassis ground is the return cable (
+).
- Secure each power cable lug to the terminal with the flat
washers and screw (see Figure 9).
Apply up to 27.4 lb-in. (3.1 Nm) of torque to each screw. Do not overtighten
the screw. (Use a number 2 Phillips screwdriver.)
Secure the positive DC source power cable lug to the return (
+) terminal.Secure the negative DC source power cable lug to the input (
–) terminal.
Caution Ensure that each power cable lug seats flush against the surface of the terminal block as you are tightening the screws. Ensure that each screw is properly threaded into the terminal. Applying installation torque to the screw when improperly threaded may result in damage to the terminal.
Caution The maximum torque rating of the terminal screws on the DC power supply is 27.4 lb-in. (3.1 Nm). The terminal screws may be damaged if excessive torque is applied. Use only a torque-controlled driver to tighten screws on the DC power supply terminals. Use an appropriately sized driver, with a maximum torque capacity of 27.4 lb-in. or less. Ensure that the driver is undamaged and properly calibrated and that you have been trained in its use. You may wish to use a driver that is designed to prevent overtorque when the preset torque level is achieved.
- Replace the clear plastic cover over the terminals on the faceplate.
- Connect each DC power cable to the appropriate external
DC power source.
Note For information about connecting to external DC power sources, see the instructions for your site.
- Switch on the external circuit breakers to provide voltage to the DC power source cable leads. Observe the system LED on the front of the router. If the DC power cable is correctly installed and functioning normally, the system LED lights green steadily. If the status LED indicates that the power supply is not functioning normally, repeat the installation and cabling procedures.
