Dell PowerEdge Rack Enclosure 4020S - Manual (Page 11)

Dell Inc. | Data Center Infrastructure 11
Power Distribution Unit (PDU) Installation
Rear Mount PDUs
The Dell 4220 and 2420 Rack Enclosures have provisions to mount a larger variety of Power Distribution Units
(PDUs) than the legacy rack enclosures. The biggest change is the addition of the PDU trays in the rear of the rack
enclosure. These are designed to mount different varieties of rear mount, full-height, and half-height PDUs from
various suppliers. PDUs with the button mounting design are now readily accepted. Simply line up the buttons
with the teardrop holes in the PDU tray and let the PDU slide down while holding it against the PDU tray. In
addition, the large holes in the PDU trays allow you to route cables between racks. See Figure 10.
A larger array of PDUs from a variety of suppliers can mount into the Dell 4220 and 2420 Rack Enclosures than are
available to mount in comparable rack enclosures. PDU trays designed to accommodate rear-mount, full-height, and
half-height PDUs have been added. Button-mounting designs are now readily accepted and easy to use: simply line
up the buttons with the teardrop holes in the PDU tray and, bracing the PDU against the tray, let the PDU slide into
place. For further ease of use, large holes in the PDU trays allow cable-routing between racks. See Figure 10.
Figure 10: Rear Mount PDUs
Another benefit of the PDU trays in the Dell 2420 and 4220 Rack Enclosures is that the rear-mount PDUs are placed
further back and away from the server equipment than is the case for other rear-mount PDU racks in the same
1070mm depth class. Mounting very deep server rails such as the Dell PE1950 and PE2950/PE2970 rails onto other
racks results in rail interference with the inner PDU, whereas the user avoids this interference without sacrificing
floor space by mounting these rails onto the Dell 2420 and 4220 Rack Enclosures. See Figure 11.