Ifm electronic sl5101 airflow monitor sensor relay output ifm electronic sl5101 this airflow sensor is used for monitoring airflow and providing a relay output when flow is present within the range 1 to 10m s the sensor has a cylindrical body and a titanium sensor and the process status is indicated by two leds green for flow present and red for no flow within the setting range the sensor also features a power on delay time and an adjustable response time ifm sl5101 airflow monitor sens