Detecting if AC appliance is powered

winner10920:
Remember the peak voltage of ac is 1.41 times the rms, the peak voltage can cause the sielectric to breakdown even tho you dont think of it
so 120rms is 169 p2p(peak to peak) and 240rms is 339p2p
So for 240 you need a cap rated for probably 400 to be safe

Actually 120vac RMS = 169 vac Peak = 339 vac peak to peak

240vac RMS = 339 vac Peak = 678 vac peak to peak

Peak and peak to peak are two different measurement values.
Lefty