Introduction S500 GSM data logger was designed to monitor temperature & humidity with capability to send alarming message to phone numbers set up by customers when temperature data is out of pre-definded limits; and will send good news message when data is back within pre-defined limits. In addition,customer can get real-time data message by calling phone number in the logger. This series use original sensor import from America or Switzerland, has high accuracy and stable. The user can also calibration the instrument by deviation. Features: Message alarm function : if the data exceed the limit that user set up, deivce will send alarm message. Frequency range :GSM850/900/1800/1900MHz Built-in sound & light alarm function: when the data exceed the limit that user set up, device will buzzer and light alarm. Get real time data by dialing the phone number that user put in the logger. Large LCD display temperature , number of data stored as well as time simultaneously. Easy to operate,USB interface, download data to PC via USB cable. MAX/MIN function key to show the maximum/minimum value Applications It has been widely applied in agricultural research fields ,electronics, food industry, medical industry ,environmental protection and laboratory, etc.