OUT580R uses a Hall-Sensor to measure the oil level. A magnetic float changes its position according to the oil level, not prone to errors by foaming or light. The hall sensor converts these magnetic field changes into an equivalent signal, which is used by the electronic controller to open or close an external solenoid valve which feeds missing oil directly into the compressor sump. If the oil level drops into the red zone the OUT580R generates an alarm signal and the alarm contact (SPDT) changes into alarm state. The latter may be used to shut down the compressor. In the Alarm status the OUT580R is still feeding oil into the compressor. If the oil level comes back to normal, the Alarm will be reset.