Removing An Mx2000 Router Dc Power Distribution Module (240 V China) - Juniper MX2020 Hardware Manual

Removing an MX2000 Router DC Power Distribution Module (240 V China)

Before you remove a PDM, be aware of the following:
NOTE: The minimum number of PDMs must be present in the router at all times.
WARNING:
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.
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.
1. Switch off the dedicated customer site circuit breaker for the PDM being removed. Follow your site's
procedures for ESD.
2. Make sure that the voltage across the DC power source cable leads is 0 V and that there is no chance
that the cables might become active during the removal process.
3. Verify that the LEDs on the PDM to be removed are not lit.
4. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to
one of the ESD points on the chassis.
5. Move the DC circuit breaker on the power input source to the OFF position.
6. Starting at one end of the PDM, unplug all the power cords. Press the latch on the side of the power
cable before pulling it out. See
Before performing DC power procedures, disconnect all power sources.
To maintain proper cooling and prevent thermal shutdown of the operating
Figure 146 on page 326.
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