Connecting AC Power to an MX2000 Router with Three-Phase Wye AC Power Distribution Modules

CAUTION:

Do not mix AC and DC power distribution modules (PDMs) within the same router.

Note:

Ensure that you have connected the chassis to earth ground. See Grounding an MX2000 Router.

Warning:

Power connections must be performed by a licensed electrician only.

To connect an AC power cord to an AC power source:

Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to an approved site ESD grounding point. See the instructions for your site.
Switch off the dedicated customer-site circuit breakers. Ensure that the voltage across the AC power source cable leads is 0 V and that there is no chance that the cable leads might become active during installation.
Detach the ESD grounding strap from the approved site ESD grounding point, and connect the strap to one of the ESD points on the chassis.
Move the power switches on all the power supply module (PSM) faceplates to the off (O) position.
Verify that the correct three-phase wye PDMs are installed and secured in the chassis before connecting power cables.
Note:
The power cables must be uninstalled and removed from the three-phase wye PDM before removal of the PDM from the chassis.
Using a number 2 Phillips (+) screwdriver, unscrew the four captive screws located on the either side of the metal AC wiring compartment (four screws total on each PDM).
Remove the metal cover of the metal AC wiring compartment.
Unscrew the retaining nut from the AC power cord.
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 compartment.
Connect the wires to the AC terminal block on the three-phase wye AC PDM (see Figure 1). Loosen the input terminal or grounding point screw, insert each wire into the grounding point or input terminal, and tighten the screw (see Table 1 for approved AC wire gauge).
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.

To connect wires to 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 1: 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 series 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 you are using your own cable, make sure you use the proper connections.

To connect wires to 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) and 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:
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 results in the cable clamps not tightening properly.

Warning:
Power connections must be performed by a licensed electrician only.
Verify that the power cable 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. Apply between 10 lb-in. (1.13 Nm) to 12 lb-in. (1.35 Nm) of torque to each screw. Do not overtighten the screws.
Use the provided plastic cable tie to fasten the AC power cord to the PDM.
Verify that the AC power cord does not touch or block access to router components, and that it does not drape where people could trip on it.
Repeat the procedure for the other three-phase wye AC PDMs.

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

Connecting AC Power to an MX2000 Router with Three-Phase Wye AC Power Distribution Modules

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