![](/images/new-backgrounds/1062747/6274759x1.webp)
Glossary
The glossary contains terms and acronyms that are used in this manual. For definitions of point database descriptors, see Chapter 3 - Point Database, in this manual. For definitions of commonly used terms as well as acronyms and abbreviations associated with the APOGEE Automation System, see the Technical Glossary of Building Controls Terminology and Acronyms,
AI
Analog Input. An AI point is a physical point which accepts a continuous variable signal.
algorithm
Mathematical formula used to calculate an output value using varying inputs.
centralized control
The type of control offered by a controller that is connected, by means of a Floor Level Network (FLN), with an APOGEE field panel.
control loop
A PID algorithm which is used to control an output based on a setpoint and an input reading from a sensor.
CV
Constant Volume.
DDC
Direct Digital Control.
DI
Digital Input. A DI point is a physical output point which accepts a
DO
Digital Output. A DO point is a physical output point which generates a
22 | Siemens Building Technologies, Inc. |