RSI51 provides information on the current light intensity setting in the runway lighting system and on the current runway-in-use setting.
RSI51 collects the runway light intensity data from a runway lighting system switch or from relays that are normally located in air traffic control towers. RSI51 converts the switch or relay data to a message and sends it to the Vaisala AviMet system. In AviMet, this data is converted to the corresponding runway light intensity setting value which is defined in the AviMet configuration file. The runway light intensity information is integrated to the AviMet RVR calculations. The AviMet system can use the runway-in-use information to indicate the active runway.