... by user from 1~255minutes; The GPRS Temperature Logger S264 is an economical and practical solution for multipoint temperature ... Center Datasheet.Functions & Features of the GPRS Temperature Logger S264:GPRS Data Transmission, no distance limited;Transmission span time is ... Modbus TCP protocol. Specifications of the GPRS Temperature Logger S264:Rated Voltage: 9~30VDC 1A Standby current: 1.1mAWorking ...