Chapter 16
A(n) ____ element opens an electrical circuit when the temperature rises
Below-atmospheric-pressure
Which type of bimetal device expands or contracts and tilts a mercury switch that serves as the electrical contact between wires?
Bourdon tube
The term for the present condition in a conditioned space is the ____
Control point
A control system's ____ is the difference between the cut-out value and cut-in value
If affects a systems average temperature
Which type of pressure motor control regulates compressor operation to maintain a specific evaporator pressure?
Low pressure motor control
If the low side pressure drops below a safe limit due to refrigerant loss or an evaporator freeze up, a(n)______switches off the compressor motor.
Low pressure safety control
Sometimes called error, the deviation between set point and control point is the ___
Offset
Which of the following device does not operate on electromagnetic principles?
PTC relay
The set of numbers between and including a control system's cut-in and cut-out values is called the systems
Range
In control systems, the desired condition is called the ____
Set point
The type of circuit diagram that shows the components and connections arranged in the order that they activate during circuit operation is a ______ diagram
ladder
The type of circuit diagram that show the approximate physical location of components in relation to each other is a _____________ diagram
pictorial
The temperature or pressure value at which a device begins operation is it
Cut-in
The temperature or pressure value at which a device ceases operation is it
Cut-out
A____relay is operated by the change in current flow through a motor run winding
Current
Sensing bulbs typically use a bellows or ___ to open and close contact points as their internal pressure changes
Diaphragm
A control system's ____ is the difference between the cut-out value and cut-in value
Differential
Reducing a systems cut-out temperature without changing its cut-in temperature is an example of ____.
Differential adjustment
If a cooling system 's cut-in temperature is decreased, but its cut-out temperature stays the same, which of the following is true?
The average temperature decreases
The three main components used in a HVACR control system
controlled device, controllor, and sensor
Which of the following devices is not used as a temperature sensor in thermostatic motor controls?
fuse