Breakage of electrical components inside is prevented when live wire insertion-and-removal is performed after inhibition of an increase in costs.A coin processing device 1 includes a coin sorting unit 3, a coin housing unit 2, and a harness 4. The coin housing unit has a first connector 21 including a first terminal TH2, a second terminal TL1, and a first ground terminal TG1. The coin sorting unit includes: a second connector 31 coupled to the first connector through the harness, the second connector 31 including the third terminal TH4 to which a high voltage is supplied through the first terminal, a fourth terminal TL2 configured to supply a low voltage to the second terminal, and a second ground terminal TG2 grounded through the first ground terminal; a low-voltage power source circuit 32 configured to generate the low voltage from the high voltage supplied to the third terminal, and configured to output the low voltage from a low-voltage output terminal 32t; and a switch circuit 34. The switch circuit disconnects electrical connection between the low-voltage output terminal and the fourth terminal in a case where a difference between a voltage at the second ground terminal and a voltage at the low-voltage output terminal has been less than a threshold value.