PURPOSE: To constitute the system so that recovery data can be stored surely in a memory of a sales data processor of a satellite machine, and a sales data processor of a master machine can initialize automatically the sales data processor of the satellite machine, when the sales data processor of the master machine initializes the memory or outputs a report.

CONSTITUTION: A master electronic charge scale 1 transmits a close command to all satellite electronic charge scales 2, 3 before executing a summing processing and a report output, transmits an open command to all the satellite electronic charge scales 2, 3 after clearing a summing memory of a RAM, and on the other hand, all the satellite electronic charge scales 2, 3 become a stand-by state of the open command by receiving the close command, and clear the summing memory of each own RAM by receiving the open command.