Dell PowerEdge Rack Enclosure 4220 - Manual (Page 6)

Cable Routing Procedures for the Dell PowerEdge T320 & T420 Systems
6
1.3. Installing the CMA
The CMA can be installed on either the rear right or rear left side of the rails as described in the CMA
Installation Instructions. Mounting the CMA on the side that is opposite of the power supplies (left-side
mount) is recommended; otherwise, the CMA must be partially disconnected in order to remove the
outer power supply. Refer to Section 2 for details on power supply replacement.
NOTE: If you are installing fiber-optic cables in the CMA, a cable bend radius of at least 1 inch must be
maintained throughout the length of the cable. It is recommended that fiber-optic cables be routed on
the exterior of the cable bundle to increase the bend radius of the fiber-optic cables through the CMA.
Additionally, a large amount of slack at the entrance and exit of the CMA is recommended.
1.3.1. Left-side mounting instructions
1. Install the CMA on the rear left side of the rails by attaching both CMA housings to the attachment
brackets on the rails as described in the CMA Installation Instructions.
2. Route the cables through the CMA while avoiding twisting the cables. Use the hook-and-loop straps
on the CMA to secure the cables.
3. If the cable bundle includes a keyboard, video, and mouse system interface pod (KVM SIP), it can
be placed inside the CMA basket.
4. Once you have routed all of the cables through the CMA, dress the cable slack between the back of
the system and the entrance of the CMA using the tie wraps provided in the CMA kit.
5. Clip off the excess length of material from the tie wraps. Make sure that the heads of the tie wraps
are positioned so as to avoid interference with adjacent systems. Return the CMA to the closed
(retracted) position.
6. Extend the system out of the rack to verify that there is sufficient slack in the cables on both ends
of the CMA.
See Figure 4 for an example of a completed left-side mounted CMA installation.
Left-side mounted CMA installation (preferred) Figure 4.
NOTE: Do not store excess cable
slack inside the CMA. The cables
may protrude through the CMA,
thus causing binding and
potentially damaging the cables.
Cables entering the CMA
should have a small amount
of slack to avoid cable strain
when the CMA is extended.
KVM SIP can be placed
inside the CMA basket.