With the logging system you can record measured values from up to 50 temperature and air humidity sensors the sensors are connected wirelessly with the base receiver at the usb port of your pc and can be distributed almost everywhere in the house the radio range is max 100 m in open space the base station stores the received data in the internal memory even with the pc switched off the voltage supply is done via usb or independently via an optional mains unit batteries and mains unit not i