What type of actuator configuration is defined by keeping one side of the diaphragm open to atmosphere?

A single-acting actuator is configured in such a way that one side of the diaphragm is open to the atmosphere, while the other side is pressurized. This allows the actuator to move in one direction when pressure is applied, typically via pneumatic or hydraulic fluid. The atmospheric side provides a reference point for movement, enabling the actuator to return to its original position when the pressure is released.

This design is efficient for applications where only unidirectional movement is necessary, as it simplifies the mechanism and reduces the need for complex operating systems. In contrast, double-acting actuators utilize pressure on both sides of the diaphragm, allowing for movement in both directions and thus providing more control in applications that require complex motion. Similarly, reverse acting actuators do not fit the criteria since their operation depends on the movement being opposite to conventional actuation.

Understanding single-acting actuators is crucial in refrigeration and HVAC systems, where they are often used for controlling valves and dampers that only require a single input action to operate effectively.