•
The cable with very high resistance (indicating an open circuit) to chassis ground is negative (–) and
will be installed 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 power
supply.
3. Ensure that the input 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 251 and “DC Power Electrical Safety
Guidelines” on page 245.
4. Ensure that the power supplies 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 76 on page 292).
6. Remove the screws on the terminals 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 on them.
7. Connect each power supply to the power sources. Secure power source cables to the power supplies
by screwing the ring lugs attached to the cables to the appropriate terminals by using the screw from
the terminals (see Figure 76 on page 292 and Figure 77 on page 293 ).
The QFX5100 is designed to operate with a DC power supply that has a single, non-redundant, feed
input. For source redundancy, two DC power supplies must be installed in QFX5100; connect source
(A) to one power supply and connect source (B) to the second power supply. This configuration provides
the commonly deployed A/B feed redundancy for the system.
290
To Next Page
Loading...
