The AC working voltage (ACWV) of a capacitor is always .707 x the DCWV.
This is because the maximum AC voltage applied to a capacitor must not exceed
the DCWV of that capacitor.
In an AC circuit, when Emax = 100 volts, Eeff = .707 x 100 volts = 70.7 volts. See
A capacitor rated at 150 DCWV has an ACWV of
A capacitor rated at 200 DCWV is placed in an AC circuit with an Eeff of 176.75
volts rms. The capacitor goes:
Why did the capacitor blow?