Direct Digital Control Concepts

DDC stands for Direct _______ Control?

In an open loop control system, where is the input device located?

• Outside the controlled space

• Inside the controlled space

• inside the unit

• There is no input device

In a closed loop system, does the input sensor directly measure and/or affect the output of the system?

What types of signals are used as DDC inputs?

• 24VAC

• open/close contacts

• 0-10VDC

• 115VAC

What are the components listed?

• controllers

• trasnmitters

• inputs

• outputs

Which of the following is an OUTPUT

• occupancy sensor

• Damper actuator

• terminal block

• GPC (general purpose controller)

This type of signal has very precise, set changes in voltage, like steps

This type of signal is more fluid, a continuous wave that varies from one second to the next

Draw an analog signal in the top half, and a digital signal in the bottom half

_______ is a device that converts AC voltage to DC voltage

• Inverter

• Alternator

• Rectifier

• VFD