Direct digital controls

Direct digital controls – direct digital controls, sometimes called digital data control, both abbreviated to DDC, enable automated control of building automation and electromechanical devices by way of microprocessors that live within the device. DDC devices typically control HVAC devices.

The DDCs use communication protocols to send operational data between each other – in most cases LON and BACnet though new protocols have emerged in recent years. The DDC uses temperature sensors to monitor the condition of the equipment and the process it produces (too much air flowing through the AHU, not enough). Status indicators are built into the display noting alarms or servicing needs.

With DDC throughout a building, a building automation system can be connected to the DDC network to add monitoring of other systems. Once controls contractors are hired to upgrade HVAC controls to DDC, their possibilities for continued engagement on that building expand tremendously. Opening devices up to more fine-tuned control by technicians and facility managers enhances their ability to troubleshoot and offer preventive services ultimately increasing occupant comfort and building efficiency.

Related links:

Designing a DDC system

Introduction to Direct Digital Controls

Past, present and future of DDC for building automation, from Automated Buildings