I'm in the Los Angeles area (Whittier), I came up with 250VA as appropriate also, My choice would also be a 500VA however I'm doing it for a really good friend, business is slow for him and I promised to help him.
Thank You all for your comments, I do have a 208 system and it does drop below 215V at times, And I will use this formula to size and purchase the transformer for a 9A motor. Any ideas where I could find a cheap one, possibly used?
What is the minimum starting Voltage for a 240V rated motor on a compressor? I have 215V line voltage and I thought of using a 24V buck/boost transformer to boost the voltage 24 volts.