Juniper ACX5448-D Hardware Manual page 102

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" on page
4. Ensure that the 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
6. Remove the screws on the terminals by using the screwdriver. Save the screws.
WARNING:
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 67 on page 105).
The ACX5400 router is designed to operate with a DC PSM that has a single, non-redundant, feed
input. For source redundancy, you must install two DC PSMs in the ACX5400; connect source (A) to
one PSM and connect source (B) to the second PSM. This configuration provides the commonly deployed
A/B feed redundancy for the system.
The terminal block of the PSM has four terminals labeled V+, V+, V–, and V– for connecting DC power
source cables labeled positive (+) and negative (–). The V+ terminals are shunted internally, as are the
V— terminals.
CAUTION:
a 2-pole circuit breaker.
Do not connect two sources to a single PSM because doing so can potentially
cause circulating current in feed wires whenever there is any difference in the
voltage of the two sources.
a. Secure the ring lug of the positive (+) DC power source cable to the V+ terminal on the DC PSM.
b. Secure the ring lug of the negative (–) DC power source cable to the V– terminal on the DC PSM.
Figure 67 on page 105).
Ensure that the power cables do not block access to device
The connection between each power source and PSM must include
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