FSD Actuators, Controls & Automatic Operation 2

Question 1

What is the purpose of end switches (limit switches) installed on smoke damper actuators?

Accepted Answer

To provide position feedback confirming the damper has fully opened or closed

Answer

To prevent the actuator motor from overheating

Answer

To adjust the torque output of the actuator

Answer

To connect the damper to the pneumatic air supply

Question 2

In a pneumatic actuator system for smoke dampers, what provides the operating force to move the damper blades?

Accepted Answer

Compressed air from a central air supply

Answer

An electric motor

Answer

A spring-loaded mechanism only

Answer

Gravity acting on a weighted blade assembly

Question 3

What control component acts as the central hub that receives fire alarm signals and sends commands to smoke damper actuators?

Accepted Answer

The Fire Alarm Control Panel (FACP)

Answer

The HVAC zone thermostat

Answer

The building differential pressure sensor

Answer

The exhaust fan variable frequency drive (VFD)

Question 4

Why is selecting the correct 'torque' rating critical when specifying a damper actuator?

Accepted Answer

It ensures the actuator can apply sufficient rotational force to overcome blade resistance under airflow conditions

Answer

It determines the speed at which the damper blades move

Answer

It sets the electrical current consumption of the actuator during operation

Answer

It defines the temperature at which the actuator will fail open

Question 5

What does a 'two-position' actuator do in a smoke damper application?

Accepted Answer

Moves the damper to either the fully open or fully closed position only

Answer

Modulates the damper between fully open and a partially open position

Answer

Controls two separate dampers with a single actuator

Answer

Operates the damper at two different stroking speeds

Question 6

After a fire alarm event, how are smoke dampers typically reset to restore normal HVAC operation?

Accepted Answer

They are manually reset from the fire alarm panel by authorized personnel

Answer

They reset automatically on a timer after the alarm clears

Answer

They reset automatically when the HVAC fan restarts

Answer

They require physical replacement of the actuator after each event

Question 7

What is the typical supply voltage used to power electric actuators on smoke dampers in commercial building control systems?

Accepted Answer

24V AC/DC or 120V AC

Answer

12V DC only

Answer

240V AC only

Answer

480V AC three-phase