How can Geist use an L22 plug that is rated at 277/480V on a PDU that is rated at 230/400V?

How can Geist use an L22 plug that is rated at 277/480V on a PDU that is rated at 230/400V?

The L22 plug has been approved for use @ 230/400V by UL. The nameplate rating of the PDU identifies the 230/400V rating in addition to labeling by the plug.