The Series 300/305 Airflow Switch is a line of highly reliable solid-state electronic switches, designed to monitor air velocity in critical environments such as cleanrooms and semiconductor fabrication facilities, and as well as in traditional electronic enclosures. These compact, easy-to-install units detect loss of airflow below a pre-programmed setpoint, and provide a fast and distinct warning of airflow deterioration. Designed to replace traditional "sail" or "vane" switches, the Series 300 air velocity switch offers unparalleled resistance to shock and vibration. The Series 300 may be either uni-directional or bi-directional. The uni-directional model discriminates between forward and reversed airflow, indicating a fault if the airflow direction reverses. The bi-directional model accepts airflows from either of two opposing directions; it triggers an alarm when airflow falls below the setpoint. The output of the Series 300 can be used to drive computer logic or it can activate alarms, relays or other circuits. For normally-open switches, the air velocity above the trip point means that the switch will stay "open".