... portUSB portTransmission5VDC,12VDC,24VDC auxiliary power supply for sensors. USB port: plug and play. Support 1GB,2GB,..USB flash driveCommunication: RS485,RS232, MODBUS-RTU ... performance and quality paperless recorder, temperature recorder, temperature and humidity recorder, paperless chart recorder, temeprature data logger KH300B Universal Paperless USB/Modbus Temperature and Pressure Data ...