Juniper ACX5448, Быстрый старт

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To connect DC power to an ACX5400 router:
1. Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap
to the ESD point on the chassis.
2. Verify that the DC power cables are correctly labeled before making connections to the power supply. In a typical
power distribution scheme where the return is connected to chassis ground at the battery plant, you can use a multimeter
to verify the resistance of the –48V and RTN DC cables to chassis ground:
•
The cable with very low resistance (indicating a closed circuit) to chassis ground is positive (+). You install this cable
on the V+ (return) DC power input terminal.
•
The cable with very high resistance (indicating an open circuit) to chassis ground is negative (–). You install this cable
on the V– (input) DC power input terminal.
CAUTION: You must ensure that power connections maintain the proper polarity. The power
source cables might be labeled (+) and (–) to indicate their polarity. There is no standard color
coding for DC power cables. The color coding used by the external DC power source at your site
determines the color coding for the leads on the power cables that attach to the DC power input
terminals on each PSM.
3. Ensure that the input 2-pole circuit breaker is open so that the voltage across the DC power source cable leads is 0 V
and that the cable leads do not become active while you are connecting DC power.
NOTE: The V+ terminals are referred to as +RTN, and V– terminals are referred to as –48 V in DC Power
Wiring Sequence Warning.
4. Ensure that the DC PSMs are fully inserted in the chassis.
5. Remove the terminal block cover. The terminal block cover is a piece of clear plastic that snaps into place over the
terminal block (see Figure 41 ).
6. Remove the screws on the terminals by using the screwdriver. Save the screws.
WARNING: Ensure that the power cables do not block access to device components or drape
where people can trip over them.
7. Connect each PSM to the power sources. Secure power source cables to the PSMs by screwing the ring lugs attached
to the cables to the appropriate terminals by using the screw from the terminals (see Figure 41 ).
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