Server Technology takes a unique approach to the placement of the outlets on the power strip with a method called "Alternating Phase". Traditional PDUs have the X, Y, and Z phases grouped together: X,X,X; Y,Y,Y; Z,Z,Z. In an Alternating Phase configuration, those phases are grouped X,Y,Z; X,Y,Z; X,Y,Z. Plugging into a different phase is then a matter of inches, not a long power cord run to the bottom of the rack. To get a visual, take a look at our HDOT Alternating Phase Flyer to see pictures of the resulting differences between the two methodologies.
Alternating phase outlets alternate the phased power on a per-outlet basis instead of a per-branch basis. This allows for shorter cords, quicker installation and easier load balancing for 3-phase rackmount PDUs.