Get phase monitors for your condensing units. There’s nothing more annoying than loosing a compressor due to your poco’s incompetence when the compressor would be just fine if something locked it out as soon as the power got weird.

I did a compressor change out on a package system last year because while we apparently sprung for all sorts of other “options” on the machine apparently the line was drawn on a $48 phase monitor. Our cheaper machines had them and rode out our service being single phased, and the package units stage two was thankfully off at the time; but we still had few thousand dollars of compressor needlessly converted to a piece of scrap metal.