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Ralph Mowery

In article ,
says...
Actually the proper caps are 115 volt caps. Seems weird on a 220 volt
motor but if you look at a wiring diagram for a dual voltage, 110/220
volt capacitor start motor you will see why. The caps only ever see
110 volts. It turns out that the capacitance is so high because the
motor is meant for starting high torque loads, like an air compressor,
which is what it doing. Since Grainger paired this compressor and
motor I guess they knew what they were doing.
Eric

As the voltage is usually over 120 volts ( at least here at my house I
monitor the voltage and it seems to run from 119 to 124) much of the
time seems the 115 volt capacitor is slightly low now. Most of the
places I see recommend replacing the capacitors on the 240 volt motors
with some around 400 volts, but those are the run capacitors.