Closeness of a housing is maintained in a normal handling state, and electric power shortage is solved to perform prompt action by quick charge in emergency situations. Normally an electronic cassette is loaded in a cradle to charge a battery by a non-contact charging function. In a case of contact charge, a pair of electrodes and a pair of terminals are brought into contact with each other by removing a packing, and the battery is charged in a state where wiring is physically connected. Therefore, energy efficiency is better compared with the non-contact charge, and the charge can be performed in a short time.