Installing an MX2000 Router Three-Phase Wye AC Power Distribution Module

Each three-phase wye AC PDM weighs approximately 12 lb (5.44 kg). To install a three-phase wye AC PDM:

Warning:

Before performing AC power procedures, ensure that power is removed from the AC circuit. To ensure that all power is off, locate the circuit breaker on the panel board that services the AC 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 PDM slot must contain either a PDM or a blank panel. If you remove a PDM, you must install a replacement PDM or a blank panel shortly after the removal.

Note:

After powering off a PDM, wait at least 60 seconds before turning the circuit breaker back on.

Note:

The PDMs are hot swappable in a redundant configuration. However, you cannot convert to a DC configuration while the system is on.

Make sure that the voltage across the AC power source cord is 0 V and that there is no chance that the cord might become active during the installation process.
Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
[Optional]—If you are switching from a DC PDM to an AC PDM, see Converting an MX2000 Router Between AC and DC Power for instructions on how to change the setting on the internal bar of the power distribution unit (PDU) cage to AC.
Pull the locking levers on either side of the faceplate away until they stop.
Using both hands, slide the PDM into the chassis until you feel resistance (see Figure 1, Figure 2, or Figure 3.
Figure 1: Installing a Three-Phase Wye AC PDM (MX2020)

Figure 2: Installing a Three-Phase Wye AC PDM (MX2010)

Figure 3: Installing an Three-Phase Wye AC PDM (MX2008)
Push the lock levers completely in until they make contact with the PDM faceplate.
Tighten the two captive screws on the locking levers of the PDM faceplate to secure the PDM in the chassis.
Using a number 2 Phillips (+) screwdriver, loosen the four screws on the cover of the metal wiring compartment that protects the AC terminal block.
Remove the cover of the metal AC wiring compartment.
Unscrew the retaining nut from the AC power cord.
Place the retaining nut inside the metal wiring compartment.
Insert the wires of the AC power cord through the hole of the retaining nut and rubber grommet.
Insert the wires of the AC power cord through the hole of the metal wiring compartment.
Connect the wires to the AC terminal block on the three-phase wye AC PDM (see Figure 4). Loosen each of the input terminals or grounding point screws, insert the wire into the grounding point or input terminal, and tighten the screw (see Table 1 for approved AC wire gauge).
To insert wires into the terminal block that serves six PSMs:
1. Insert the grounding wire into the grounding point labeled GND.
2. Insert the wire labeled L1 into the input terminal labeled A1.
3. Insert the wire labeled L2 into the input terminal labeled B1.
4. Insert the wire labeled L3 into the input terminal labeled C1.
5. Insert the wire labeled N into the input terminal labeled N1.
Figure 4: Connecting Power to a Three-Phase Wye AC Power Distribution Module

Note:
The three-phase wye AC PDM terminal blocks will be flipped depending on which slot the PDM gets plugged into.

Note:
The color of each AC power wire might vary. The MX2000 chassis is not sensitive to phase rotation sequence—either CW or CCW will operate correctly.

CAUTION:
Wire label configuration is for Juniper Networks supplied cable only. If using your own cable, make sure you use the proper connections.

To insert wires into the terminal block that serves three PSMs:
1. Insert the grounding wire into the grounding point labeled GND.
2. Insert the wire labeled L1 into the input terminal labeled A2.
3. Insert the wire labeled L2 into the input terminal labeled B2.
4. Insert the wire labeled L3 into the input terminal labeled C2.
5. Insert the wire labeled N into the input terminal labeled N2.
Warning:
To protect power supplies from input voltage that might be caused by mis-wired PDMs, before reinstalling the metal cover to the wiring compartment, apply AC voltage to the PDM (with disengaged PSM) to make sure that two LEDs on the PDM are lit green and that the AC voltage between AC terminal blocks A1-N1, B1-N1, C1-N1, A2-N2, B2-N2, and C2-N2 for three-phase wye PDM is not more than 264 VAC when measured with a digital voltage meter (DVM). Then turn off the AC breaker de-energizing the PDM and install the metal cover and engage all AC PSMs.

Note:
The terminal connections have either slotted screws or hex screws. Use a 1/4-in. slotted screwdriver for the slotted screws. Use a 5/32-in. (4 mm) Allen wrench for the 5/16-in. hex screws.

Note:
Three-phase wye AC wire assembly kits can be purchased from Juniper Networks.

Table 1: Supported Three-Phase Wye AC Wire Gauge
Wire Gauge Description

5 x 10-AWG or equivalent

5 conductor wires, each wire is 10-AWG

Note:
We recommend that you use the proper gauge wire in order for the cable clamps to hold the AC cables. Using smaller gauge wiring will result in the cable clamps not tightening properly.

Warning:
Power connections must be performed by a licensed electrician only.
Verify that the power cord wire connections are correct.
Screw the retaining nut onto the AC power cord to secure it to the metal wiring compartment.
Reinstall the metal PDM wiring cover, and using a number 2 Phillips (+) screwdriver, tighten the four captive screws on the metal AC wiring compartment.
Verify that the AC power cord is not touching or blocking access to router components, and that it does not drape where people could trip on it.
Remove the ESD grounding strap from the ESD points on the chassis. Connect the strap to an approved site ESD grounding point. See the instructions for your site.
Connect the AC power cord plug to the power source.
Switch on the customer-site circuit breakers to provide voltage on the AC power cord.
Remove the ESD grounding strap from the approved site ESD grounding point. See the instructions for your site. Reconnect the strap to one of the ESD points on the chassis.
Verify that the LED on the PDM faceplate is lit steadily, indicating that the AC terminal block is receiving power.

Wire Gauge	Description
5 x 10-AWG or equivalent	5 conductor wires, each wire is 10-AWG