Juniper MX240 - Connecting an MX240 DC Power Supply Cable

4. Route the power cord appropriately. Verify that the power cord does not block the air
exhaust and access to router components, or drape where people could trip on it.
5. Switch the AC input switch on the each power supply to the on (|) position and observe
the status LEDs on the power supply faceplate. If the power supply is correctly installed
and functioning normally, the AC OK and DC OK LEDs light steadily, and the PS FAIL
LED is not lit.
Related
Documentation
Disconnecting an MX240 AC Power Supply Cord on page 338•
• Preventing Electrostatic Discharge Damage to an MX240 Router on page 444
• AC Power Cord Specifications for the MX240 Router on page 140
• MX240 AC Power Electrical Safety Guidelines and Warnings
Connecting an MX240 DC Power Supply Cable
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 connect a power cable for a DC power supply:
1. Locate a replacement power cable that meets the specifications.
2. Verify that a licensed electrician has attached a cable lug to the replacement power
cable.
3. Verify that the INPUT OK LED is off.
4. Secure the power cable lug to the terminal studs, first with the flat 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 75 on page 208). Do not overtighten the nut. (Use a 7/16-in. [11 mm]
torque-controlled driver or socket wrench.)
CAUTION: Ensure that each powercable lug seatsflushagainst the surface
of the terminal block as you are tightening the nuts. Ensure that each nut
is properly threaded onto the terminal stud. The nut should be able to spin
freely with your fingers when it is first placed onto the terminal stud.
Applying installation torque to the nut when improperly threaded may
result in damage to the terminal stud.
207Copyright © 2017, Juniper Networks, Inc.
Chapter 17: Connecting the MX240 Router to Power