S6061NS-30/40Nm Non Spring Return Damper Actuator

A non-spring return electric damper actuator (also called ”non-spring return” or “motorized damper actuator”) is a device used in HVAC systems to control the position of dampers (airflow-regulating plates) without a built-in spring mechanism. Unlike spring return actuators, which rely on a spring to revert to a default position (e.g., closed) when power is lost, non-spring return actuators hold their last position when power is cut.