PROBLEM TO BE SOLVED: To make a radiation detector assembly last long while securing easiness of return from a standby state by supplying electric power intermittently at standby.SOLUTION: The radiation detector assembly includes: a radiation detection instrument 60 which detects radiation, converts the detected radiation into a charge, and outputs a radiation image data from the converted charge a cassette control section 92 which controls the drive of the radiation detection instrument 60 and a battery 96 which supplies power to the cassette control section 92, wherein the battery 96 includes a battery control section 96B which controls to supply power to the cassette control section 92 intermittently at standby.
