In the schematic with the capacitor in series with the optocoupler's LED, what is the function of the capacitor? I know you can limit AC current with a series capacitor, but why is the resistor alone not enough?
In the schematic with the capacitor in series with the optocoupler's LED, what is the function of the capacitor? I know you can limit AC current with a series capacitor, but why is the resistor alone not enough?