Cisco Carrier Routing System CRS-1 Installation Manual page 42

Installing a DC Power Shelf
Note
On the PIM, use a 10-mm hex socket wrench to hook up the DC input power cables. Connect the four
Step 11
60 A DC cables (two cables per input) on the left to one wiring block, and the four 60A DC cables on
the right to the other wiring block (see
Note
Color Coding of the Source DC Power Cable. The color coding of the source DC power cable leads
depends on the color coding of the site's DC power source. Typically, green or green and yellow
indicates that the cable is a ground cable. Because no color code standard exists for the source DC
wiring, you must ensure that the power cables are connected to the DC-input power shelf terminal studs
in the proper positive (+) polarity and negative (–) polarity.
DC Cable Polarity Labels. Sometimes, the source DC cable leads might have a positive (+) or a
negative (–) label. This label is a relatively safe indication of the polarity, but you must verify the
polarity by measuring the voltage between the DC cable leads. When making the measurement, the
positive (+) lead and the negative (–) lead must always match the (+) and (–) labels on the power shelf.
Figure 2-16 DC Power Shelf Cable Cabling
+
B 1
(R TN )
Reattach both wiring block covers (see
Step 12
a.
b.
Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Installation Guide
2-18
When wiring the power shelf, be sure to attach the ground wire first. When removing the wiring,
be sure to remove the ground wire last. The ground wire must be attached with a torque value of
30 in-lb.
The DC input power cables should also be attached with a torque value of 30 in-lb.
–
+
B 0
(-4 8V /-6
0V ) –
(R TN )
(-4 8V /-6
0V )
O N
S ID E B
B 1
B 0
Snap the cover over the wiring block so that it snaps closed.
Use a number 1 Phillips screwdriver to tighten the capture screw.
Chapter 2
Figure 2-16).
+
A 1
S ID E A
–
(R TN )
O N (-4 8V /-6
A 1
A 0
Figure 2-16).
Installing and Removing Power Components
+
A 0
0V ) –
(R TN )
(-4 8V /-6
0V )
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