Juniper MX2010 Hardware Manual page 593

CAUTION:
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 switch
from one type of PDM (AC or DC) to another while the system is on.
Each three-phase delta AC PDM weighs approximately 12 lb (5.44 kg). To install a three-phase delta AC
PDM:
1. 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.
2. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to
one of the ESD points on the chassis.
3. [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.
4. Pull the locking levers on either side of the faceplate away until they stop.
5. Using both hands, slide the PDM into the chassis until you feel resistance (see
Figure 194 on page 412Figure 195 on page
6. Push the lock levers until they make contact with the PDM faceplate.
7. Tighten the two captive screws on the locking levers of the PDM faceplate to secure the PDM in the
chassis. 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.
To maintain proper cooling and prevent thermal shutdown of the operating
412, and Figure 196 on page 413).
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