Question 1

In a fan relay (FR) circuit, if the control switch is moved to the ____, the fan will be controlled by the action of the thermostat.&#10;A) &#34;CONTROL&#34;position&#10;B) &#34;AUTO&#34;position&#10;C) &#34;ON&#34;position&#10;D) &#34;TH&#34;position

Accepted Answer

In the "AUTO" position, the fan relay will be controlled by the action of the thermostat. This means that when the thermostat calls for heating or cooling, it will signal the fan relay to turn on the fan. In the "ON" position, the fan will run continuously regardless of whether or not the thermostat is calling for heating or cooling. The "CONTROL" and "TH" positions are not typically used in a fan relay circuit.

Question 2

In a schematic, a system of equations is often used to aid in the connection of the circuit.

Accepted Answer

A schematic typically uses symbols and lines to represent the components and connections in a circuit, not a system of equations.

Question 3

Developing a wiring diagram from a schematic is the same basic procedure that is followed when installing a control system.

Accepted Answer

Both require identifying the components and connections, and then properly wiring them according to the schematic or control system diagram.

Question 4

Suppose a circuit is designed to turn off a compressor if the pressure in the system reaches a predetermined level.If the pressure becomes high enough to cause the pressure switch contacts to close, ____.

A) the CR relay coil is turned off
B) the compressor motor will connected to an auxiliary power line
C) a warning light will be turned on
D) compressor is automatically restarted by the thermostat

Accepted Answer

When the pressure switch contacts close due to high pressure, it typically triggers a warning system, such as turning on a warning light, to alert that the pressure has reached a critical level.

Question 5

In a schematic diagram, all components connected to the same line will receive ____.&#10;A) sequentially ordered numbers&#10;B) a pair of numbers for on and off positions&#10;C) the same number&#10;D) a letter corresponding to the wiring diagram

Accepted Answer

All components connected to the same line in a schematic diagram will receive the same number. This is done to show that they are all connected together and are part of the same circuit.

Question 6

A fan relay (FR) circuit is designed so that a switch can be used to turn the circuit completely off, operate the fan manually, or ____.&#10;A) operate the fan by remote control&#10;B) permit the fan to be operated by a thermostat&#10;C) turn on a warning light&#10;D) automatically reset the fan

Accepted Answer

The fan relay circuit is usually used in HVAC systems to control the operation of a fan through a thermostat. Therefore, the best choice is B, which permits the fan to be operated by the thermostat. The other options, such as remote control or warning lights, may be useful in different scenarios but are not specifically related to the fan relay circuit. Option D, automatically resetting the fan, may not be desirable, as it may cause the fan to operate when it is not needed.

Question 7

In a wiring diagram, ____.&#10;A) the numbering system is different from the corresponding schematic diagram&#10;B) any time a component is gone through, the number will be reset to the original&#10;C) a set of numbers can be used more than once&#10;D) a set of numbers can be used only once

Accepted Answer

In a wiring diagram, each set of numbers is used only once to avoid confusion and ensure accuracy in the wiring configuration.

Question 8

A double pole double-throw switch is generally marked with one common terminal, one terminal marked NC, and a third terminal marked NO.

Accepted Answer

A double pole double-throw (DPDT) switch typically has two common terminals, two normally closed (NC) terminals, and two normally open (NO) terminals, making a total of six terminals.

Question 9

Understanding the development of a wiring diagram from a schematic is a great advantage when troubleshooting existing circuits.

Accepted Answer

This statement is true. A wiring diagram shows the actual physical connections and layout of the wires in a circuit, while a schematic shows the conceptual layout of the circuit without necessarily showing the physical connections. Understanding how the conceptual circuit translates to the physical wiring can be very helpful in troubleshooting issues with the circuit.

Question 10

Once the components of the wiring diagram have been numbered with the same numbers as those on the schematic, the circuit can be connected by connecting like numbers.

Accepted Answer

This statement is correct. The numbering system on the wiring diagram is done to match the schematic, making it easier to connect the circuit by connecting components with the same numbers.

Deck 10: Developing Wiring Programs