Cisco 12008, Installation And Configuration Manual, Page: 179 / 382

Installing a Cisco 12008 3-47
Connecting Source Power to the Power Supplies
Also, before attempting to connect source power to a DC-input power supply, review the
content of the section in Chapter 2 entitled “DC-Powered Systems,” which deals with the
following topics:
•
Specifications for source DC input power (see Table 1-10 in Chapter 1)
•
Specifications of the source DC power cable and lug (see Table 2-2 in Chapter 2)
•
Dimensions of the lugs used with the source DC power cables (see Figure 2-6 in
Chapter 2)
To connect source power to a DC-input power supply, perform the following steps:
Step 1
Verify that the rotary power switch on the DC-input power supply is in the OFF
(O) position.
Caution
Before proceeding to the next step, verify that the source DC circuit breaker
servicing the source DC power cables you are attaching to the DC-input power supply is in
the OFF position. As an additional check, measure the voltage across the DC power cable
leads that you intend to connect to the power supply. The voltage reading should be zero.
Step 2
Loosen the knurled thumbscrew that secures the plastic safety cover to the
faceplate of the power supply. Slide the plastic safety cover to the right and
upward until it can be removed from the knurled thumbscrew and the two
standoffs in the power supply faceplate. Set the cover aside temporarily.
Step 3
Attach the source DC power cables to the power supply terminals in the
following order:
(a) Ground
(b)
+ (positive)
(c)
– (negative)
Note This order of connection of source DC power to the power supply
terminals must be strictly observed.