Since the early days of valve actuator use, there has been a choice between powering the actuator with electricity or pressurized fluid. Sometimes a user industry has a traditional preference for actuator power and sometimes it’s dictated by the circumstances of the application.
Deciding the best power medium for an industrial application depends on many factors such as following what has traditionally been used in the application. But with today’s sharp focus on return on investment and environmental impact, the traditional solutions now warrant closer examination.
For plants that have instrument air systems, the choice of actuator power is more flexible because electricity is usually available to power the instrument air supply. Either fluid or electric-powered actuators could be used. But there are many installations, such as well heads, pipelines or irrigation systems where an electric power supply is not available.
Where both power modes are available, then the choice comes down to other criteria and the traditional choice varies by industry and region.