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According to manufacturer, the rooftop AC unit only requires 3 conductors + ground (600V / 3 phases)

I'm pretty sure some stuff in there works on single phase (actuators, small fans, etc.)

Is there usually a transformer inside the units?
 

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According to manufacturer, the rooftop AC unit only requires 3 conductors + ground (600V / 3 phases)

I'm pretty sure some stuff in there works on single phase (actuators, small fans, etc.)

Is there usually a transformer inside the units?
...you only land the 3 phases and ground in disconnect, the unit itself is 'pre-wired' and UL approved. Don't forget about the required receptacle within 25' of unit nec 210.63
 

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I like ceiling fans & EMT
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It just so happens I have the schematic for a 5 ton, 3 phase rooftop package unit right next to me. It's been sitting on our small couch for several weeks, to my wife's dismay . . . I asked her to scan it for me and she hasnt yet so there it sits.

There is one 208v to 24v step down transformer for control circuits. Everything else in it is three phase.
 

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I like ceiling fans & EMT
Former commercial, occasional (small) residential
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I forgot to mention, this unit (and the 8 other similar/identical units we have) are fed by 8/3 romex with a 12 gauge ground.
 
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