When calculating wattage for different motors I would normally use 240 volts however, the motors have a range listed on them of 208-230 volts. Would I use 208, 230 or 240? Not to mention that they sometimes they even have an amperage range listed. I generally use the highest figures listed on the motor in this case 230 for voltage and what ever the highest amp rating is. This way I would think I am comparing apples to apples. If one particular motor brand did run on 208 my cost analysis would be off. Let me know if there are any other considerations.