Operating Instructions

Glossary
Glossary-2 Siemens Building Technologies, Inc.
control loop
PID algorithm that is used to control an output based on a setpoint and an input reading from
a sensor.
Datamate
Customer software tool for all controller communications. There are two versions: Datamate
Base and Datamate Advanced. Datamate Base works on an IBM-compatible personal
computer, or a handheld PC or Pocket PC™ running Windows CE. Datamate Advanced
works only on an IBM-compatible personal computer. With Datamate, you can back up,
restore, and edit any APOGEE database (but only Datamate Advanced allows you to edit
points offline).
day mode
Operational mode of a controller when it is using day temperature setpoints.
DDC
Direct Digital Control. (1) Industry-standard term for intelligent, microprocessor-based control
units in various locations throughout a facility. It may incorporate P, PI, or PID control. (2)
Electronic controller that that is programmed to provide the required control action. Differs
from an analog controller in that the digital controller initially applies a numerical value to the
incoming signal from a sensor (digitizes the input). This enables the signal to be processed
by the controller program. A digital controller program thus follows the mathematical and
logical thought process of the control program designer to arrive at the required control output
signal.
DI
Digital Input. Physical input point that accepts a two-state signal (that is, ON/OFF,
OPEN/CLOSED, YES/NO, etc.).
DO
Digital Output. Physical output point that generates a two-state signal (that is, ON/OFF,
OPEN/CLOSED, YES/NO, etc.).
English units
Foot-pound-second system of units for weights and measurements.