Damper Actuator Controls Movement of Air-Flow Regulator
Damper actuators, sometimes mistakenly called actuator dampers, are automated controls for the devices that regulate the flow of air in given confined systems. They come in several types that have unique benefits. A damper actuator is commonly used in commercial and residential heating, ventilating and air-conditioning (HVAC) systems.
Actuator-controlled dampers also have applications in industries ranging from petroleum, power generation, metals and mining to water and wastewater treatment. Open dampers mean air flows freely through a system. Closed dampers mean that it doesn't. Actuators do the opening and closing.
Manually controlling the HVAC systems of small buildings without damper actuators would be extremely laborious. In larger structures, it would be nearly impossible. Among the HVAC applications for damper actuators are:
· VAV (variable air volume) systems.
· Fire/smoke dampers.
· Mixing boxes (where the return air flow is mixed with the outside air flow).
· Exhaust dampers.
· Central fan systems.
Damper actuators usually incorporate a solenoid or solenoids, and the actuators most commonly used for HVAC systems are:
· Electric actuators: Also known as electro-mechanical actuators, an electric actuator uses electricity to power motor-driven gear trains or screws that position actuator stems, which open and close the dampers. Think of how garage-door openers use gear trains or screws to open or close the heavy door.
· Pneumatic actuators: A pneumatic actuator performs the same function but draw its energy from compressed air or another gas. That compressed gas is converted into motion. The two main forms of pneumatic devices are piston actuators and diaphragm actuators. The piston devices often are used when diaphragm actuators generate too short of a stroke and, or a too-small thrust. Diaphragm actuators are single-acting, meaning that pressure from air or gas is applied to only one side of the membrane. Piston actuators can be single or double-acting.
· Hydraulic actuators: A hydraulic actuator also serves the same purpose and closely resembles a pneumatic actuator, except it relies on compressed fluid to generate energy.
Damper actuators also have two common configurations: linear and rotary.
· Linear actuators: A linear actuator uses a non-linear motion to create a linear motion to move and position a damper.
· Rotary actuators: A rotary actuator simply relies on a non-linear motion, like that of a motor, to move and position a damper.
So what does all of this mean? Are electric damper actuators better than pneumatic or hydraulic ones, or are the hydraulic/pneumatics best? It depends on the application.
Pneumatic and hydraulic damper actuator systems are easily understood and maintained and offer basic motion with high speed capacities and strong force. They're well-suited for end-to-end applications with continuous motion. Their initial costs are low compared with electric - only about one-third - however the upkeep and overhead can be higher.
Electric damper actuators are more accurate and give true control of motion, from speed and positioning to synchronization. While electric actuators are far more precise and, depending on the motor, can operate very quietly, they generally cost more and require greater expertise to operate, maintain and troubleshoot. Good providers can help customers determine which damper actuators best suit them. Each has unique benefits.