A power control device, comprising: a first capacitor (X-CAP) to be charged by AC power during input of the AC power; a rectifier to convert the AC power to DC power; a second capacitor (E-CAP) formed at an output of the rectifier; and a discharge circuit, which includes at least one discharge resistor (Rdis), and a first switch and a second switch configured to be alternately turned on/off in response to supply and interruption of the AC power, and which discharges at least one of the first and second capacitors (E-CAP, X-CAP) via the at least one discharge resistor (Rdis), in response to turn-off of the first switch and turn-on of the second switch, wherein the first capacitor (X-CAP) is electrically connected between input lines through which the AC power is input; wherein the first switch comprises a detection circuit including a photo-coupler configured to be electrically connected between the input lines of the AC power, and turned on in response to input of the AC power and turned off in response to interruption of the AC power, wherein the first switch further comprises an RC series circuit (R1, C1) which is electrically connected in series to the photo-coupler between the input lines of the AC power, wherein the photo-coupler comprises a light emitting device connected to the RC series circuit (R1, C1), and a light receiving device configured to be turned on in response to emission of the light emitting device, wherein the second switch further comprises a detection resistor which is connected between a collector of the light receiving device and the output of the rectifier, and a resistivity of the detection resistor is greater than a resistivity of the discharge resistor (Rdis). a first capacitor (X-CAP) to be charged by AC power during input of the AC power; a rectifier to convert the AC power to DC power; a second capacitor (E-CAP) formed at an output of the rectifier; and a discharge circuit, which includes at least one discharge resistor (Rdis), and a first switch and a second switch configured to be alternately turned on/off in response to supply and interruption of the AC power, and which discharges at least one of the first and second capacitors (E-CAP, X-CAP) via the at least one discharge resistor (Rdis), in response to turn-off of the first switch and turn-on of the second switch, wherein the first capacitor (X-CAP) is electrically connected between input lines through which the AC power is input; wherein the first switch comprises a detection circuit including a photo-coupler configured to be electrically connected between the input lines of the AC power, and turned on in response to input of the AC power and turned off in response to interruption of the AC power, wherein the first switch further comprises an RC series circuit (R1, C1) which is electrically connected in series to the photo-coupler between the input lines of the AC power, wherein the photo-coupler comprises a light emitting device connected to the RC series circuit (R1, C1), and a light receiving device configured to be turned on in response to emission of the light emitting device, wherein the second switch further comprises a detection resistor which is connected between a collector of the light receiving device and the output of the rectifier, and a resistivity of the detection resistor is greater than a resistivity of the discharge resistor (Rdis).