Lenovo System x PDU Technical Reference page 62

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Mounting in EIA (U space) of rack
Mounting the DPI C19 PDU (39Y8948) in the U space of a rack requires the use of
the horizontal mounting bracket, shipped as part of the PDU accessory kit, see the
Accessory Kit section for additional information.
1 PDU will fit in 1U of rack space see figure 29.
Figure 29: DPI C19 PDU horizontal mounting in rack
Note: You must remove any horizontally-mounted Front End PDUs from the EIA
mounting space before you relocate your rack cabinet. Horizontal installation of
Front End PDUs is not supported during relocation or shipping of a rack cabinet.
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