D-7
Cisco Content Delivery Engine 100/200/300/400 Hardware Installation Guide
OL-13478-03
Appendix D Connecting DC Power Connecting DC Power to a CDE400
Warning
The DC ground connection in the CDE serves as a functional earth point to maintain the full EMI and
EMC integrity of the equipment. The purpose is to mitigate the damaging effects of electrostatic
discharge. This connection should be installed by a trained service person and the equipment is to be
installed per local code or local authority having jurisdiction (AHJ). The building ground wire should
not exceed 3 meters in length and be sized similarity to the conductors used for the DC power
connections (–48 VDC and +Return).
Step 4 Attach the +Return (red) and –48 VDC (black) DC power wires to your power source.
The CDE300 is now ready for use.

Disconnecting Power and Replacing a PM on a CDE300

Warning
The PM connectors and PMs are not hot-swappable. You must disconnect the power source from the
building before disconnecting PM wires or removing PMs from a CDE.
Should you need to replace a PM, you must first disconnect DC power and remove the PM from the CDE
chassis. Perform the following steps:
Step 1 Remove the +Return (red) and –48 VDC (black) DC power wires from your power source.
Step 2 Remove the PM ground wires (green and yellow) from the Building/PM ground stud.
Step 3 Press the butterfly lever to release the CDE from the chassis. Pull the handle and gently slide the PM
from the slot.
Step 4 Insert a new PM in the slot and make sure it is completely seated in the CDE.
Step 5 Reconnect the PM ground wires (green and yellow) to the PM ground stud as described in Step 3 of the
“Connecting DC Power to a CDE300” section on page D-5.
Step 6 Reconnect the +Return (red) and –48 VDC (black) DC power wires to your power source.
Connecting DC Power to a CDE400
The CDE400 ships fully populated with four DC PMs installed in the PM slots on the rear of the chassis;
four DC power cables are shipped separately. The chassis has one building ground stud and two PM
ground studs. The minimum cabling requirement for connecting DC power to a CDE400 is three PM
connects, but it is recommended that you use all four PM connects. Figure D-7 shows the rear view of a
fully-connected CDE400 and provides the location of the studs and PMs.