I did email the manufacturer and just wrote me back. Here is what he had to say.
Thank you for contacting Universal Lighting Technologies.
Any Triad ballast containing ‘UNV’ as part of the catalog number continuously monitors the incoming line voltage and regulates for that incoming voltage in real time as long as the line voltage is between 108V minimum and 305V maximum, and source frequency is at 60- or 50-Hz. This comes in very handy on a commercial site where the temporary power is 120V prior to commissioning of the 3-phase 277/480V power.
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