Controlling a Constant Air Volume (CAV) system typically involves regulating the airflow rate to maintain a constant volume of air supply to a space. Some of the most common methods used for CAV control include:
1. Fan speed control. The fan speed is adjusted to control the airflow rate. By varying fan speed, more or less air is delivered into the space.
2. Dampers. By adjusting the damper position manually or automatically, depending on the damper type, the desired air volume is distributed into the building.
3. Differential pressure controllers. CAV systems can also employ differential pressure control methods to maintain a constant airflow. Differential pressure sensors measure the pressure drop across filters, dampers, or other components in the system. By monitoring and controlling the differential pressure, the system adjusts the fan speed or damper positions to maintain a constant airflow rate.
Following the best HVAC practices, we designed the ACDPH series of round electrically operated CAV dampers featuring differential pressure control. The damper consists of a damper blade, integrated into a tube, that is moved or adjusted using an electric motor. The ACDPH is installed within the ductwork or ventilation system and is controlled automatically.
Below are the features of the ACDPH series:
Design: The CAV controller consists of a blade that can open or close the duct opening. The blade is made of metal to withstand the airflow and pressure. It is integrated into an ASA rigid plastic tube that is attached to the ductwork.
Electric Motor: The damper is equipped with an electric motor that drives the movement of the damper blade. The motor is based on the signals of the integrated differential pressure sensor and is supplied with 24 VDC via an RJ45 connector or a terminal block, whichever you prefer.
Control: Automatic control is based on differential pressure, volume flow or air velocity, ensuring the damper adjusts itself according to the predetermined setpoint.
This motorised CAV damper provides precise and flexible control over the airflow, differential pressure and air velocity in ventilation systems, allowing for improved ventilation efficiency, energy savings, and better environmental control.
The ACDPH is intended for use in:
Ventilation Systems: CAV control is crucial in ventilation systems to ensure the proper exchange of fresh air in a building or enclosed space. By maintaining a consistent airflow rate, these systems can remove pollutants, regulate temperature and humidity, and provide fresh air for occupants.
HVAC Systems: These systems rely on precise control of airflow to distribute conditioned air throughout a building. Consistent airflow helps achieve uniform temperature and comfort levels in different areas while optimising energy efficiency.
Industrial Processes: Many industrial processes require controlled airflow to maintain stable conditions and ensure product quality. For instance, in manufacturing facilities, consistent airflow can be necessary for cooling, drying, or preventing the accumulation of fumes or dust.
Cleanrooms: In environments such as cleanrooms, where maintaining a high level of air cleanliness is critical, constant airflow control is essential. By carefully controlling the airflow rate and direction, contaminants can be minimised, protecting sensitive processes or products like semiconductor manufacturing or pharmaceutical production.
Research Laboratories: Scientific laboratories often require precise control of airflow to maintain specific environmental conditions, such as controlling particulate levels, preventing cross-contamination, or maintaining sterile conditions.
Good airflow control and ventilation have a positive impact on occupants' health and productivity. Poor indoor air quality due to inadequate ventilation can lead to symptoms like headaches, fatigue, respiratory issues and decreased cognitive function. Sufficient airflow helps create a healthier and more productive environment.