DDC Control Module for an Air Handling UnitDDC Control Module for an Air Handling Unit – This is a direct digital controls control module for an air handler that serves some VAV boxes in office spaces for a Data Center. This DDC control module includes analog and digital inputs and analog and digital outputs to handle all the control functions necessary to control the devices and components on a large commercial air handler.

DDC Control Module for an Air Handling Unit

For example, damper actuators can be either two position or analog modulating. If the actuator is two position then a digital output sends a 24-volt signal to the damper actuator to drive the damper open or closed depending on its default position. A modulating actuator damper will get an analog signal from the DDC control module so the damper can modulate as determined by the program and inputs from other devices.

For inputs, these also can be either digital or analog where something such as a high static pressure switch would be digital so when the switch trips because of high static pressure in the air handler then the digital controller shuts down the air handler. An analog input would be something such as a temperature sensor or pressure transmitter in the ductwork. The controller reads the analog signal sent back from these devices, processes these inputs, and then sends a control signal to an output device to control the medium or process.

DDC Control Module for an Air Handling Unit

The interface offers a logical way for a programmer or user to understand how the logic in the program works for the DDC control system. By clicking on the blocks in the program and having the correct privileges one can change the parameters of the logic blocks. For example, if you want to change the temperature setpoint for a conditioned space or room you would look for the logic block that contains that set point and click on it and change it to the desired set point. With a little training, the average operator can learn how to use the DDC system including the DDC interface to maintain maintenance on HVAC equipment, troubleshoot problems with the HVAC system, and monitor temperatures and conditions in the HVAC system.

DDC Control Module for an Air Handling Unit

 DDC Logic Interface

High Performance HVAC

DDC Control Module for an Air Handling Unit

To learn more about heating systems and HVAC use this resource.

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