Juniper MX2020 Hardware Manual page 490

MX2020 3D Universal Edge Router Hardware Guide
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WARNING: Before performing DC power procedures, disconnect all power
sources. 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
position, and tape the switch handle of the circuit breaker in the
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.
Switch off the dedicated customer site circuit breaker for the PDM being removed.
1.
Follow your site's procedures for ESD.
Make sure that the voltage across the DC power source cable leads is 0 V and that
2.
there is no chance that the cables might become active during the removal process.
Switch off ( ) the DC PSMs and disengage all DC PSMs.
O
3.
Verify that the LEDs on the PDM to be removed are not lit.
4. –48V
Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect
5.
the strap to one of the ESD points on the chassis.
Move the DC circuit breaker on the power input source to the
6.
Remove the clear plastic covers protecting the terminal studs on the faceplate.
7.
Remove the nut and washers from each of the terminal studs. (Use a 7/16-in.
8.
[11 mm] nut driver or socket wrench.)
Remove the cable lugs from the terminal studs.
9.
Carefully move the power cables out of the way.
10.
Loosen the two captive screws on the locking levers, and pull away from the chassis.
11.
NOTE: PDM3/Input1
release from chassis, and
are pulled up to release from chassis.
The PDM is extended slightly away from the chassis.
12.
With both hands, grasp the two handles and gently pull the PDM straight out of the
13.
chassis.
and PDM1/Input1 locking levers are pulled down to
and
PDM0/Input0 PDM2/Input0
Copyright © 2015, Juniper Networks, Inc.
OFF
OFF position.
OFF position.
locking levers