Each transmitter has a RS485 output for communicating with remote calibrator and the Visual Pro controller Comparability to work with NO2 sensor Ability to zero-calibrate all LPG sensors Sensor offset function available 3-digit output: First alarm, second alarm and evacuation 2 analogue output: Max CO and Max LPG Error display when sensor reaches an adjustable error level Data recordable for error buffer up to 100 errors Graphical chart for Trend buffer up to 48 hours