Question 1

A target table is useful in interpreting circuit drawings and for .&#10;A)moving contacts&#10;B)reversing interchange lines&#10;C)simplifying troubleshooting&#10;D)moving large lots of motors

Accepted Answer

A target table helps in identifying the function of various components in a circuit drawing, making it easier to troubleshoot and identify faults. It does not have any relevance to moving contacts or motors, and reversing interchange lines is not a standard practice in electrical circuits. A target table can help simplify troubleshooting by providing information on what each symbol in the circuit drawing represents, making it easier to identify and fix any issues that may arise. Moving contacts and large lots of motors are not relevant to the use of a target table, while reversing interchange lines does not require a target table.

Question 2

To reverse a single-phase AC motor, either the starting or running windings connections must .&#10;A)identify a specific motor&#10;B)be reversed on the line&#10;C)be equal to the supply voltage&#10;D)have a high voltage rating

Accepted Answer

To reverse a single-phase AC motor, the connections of either the starting or running windings must be reversed on the line. This reverses the direction of the magnetic field and enables the motor to rotate in the opposite direction. The other options do not relate to reversing the motor's direction. Reversing the connections of either the starting or running windings on a single-phase AC motor is what allows for the motor to run in reverse. This is commonly done by disconnecting the motor from the power source, swapping the wire connections of either the starting or running winding, and then reconnecting the motor to the power source. The other options (identifying a specific motor, equal to the supply voltage, and high voltage rating) do not directly relate to reversing a single-phase AC motor.

Question 3

Target tables are often used in complicated circuits to simplify the interpretation of the operation of large .&#10;A)three-position selector switches&#10;B)selector switches&#10;C)master switches&#10;D)multicircuit drum switches

Accepted Answer

Target tables are typically used in complicated circuits to simplify the interpretation of the operation of large multicircuit drum switches. Target tables are used in complicated circuits to simplify the interpretation of the operation of large multicircuit drum switches.

Question 4

Throttle valves and narrow pipes can waste huge amounts of power.

Accepted Answer

Throttle valves and narrow pipes can cause pressure drops and turbulence which result in energy losses, wasting significant amounts of power. Throttle valves and narrow pipes can restrict the flow of fluid, leading to loss of energy and increase in pressure drop. This can result in lower efficiency and wasted power.

Question 5

Motors draw half as much current on high voltages as they do on low voltages.

Accepted Answer

This is due to Ohm's Law, which states that current is inversely proportional to voltage when resistance remains constant. Therefore, as voltage increases, current decreases, and vice versa. This is due to Ohm's law (V=IR), where the current (I) drawn by a motor decreases as the voltage (V) increases, assuming the resistance (R) of the motor remains constant.

Question 6

The service factor of a general-purpose motor is a(n) .&#10;A)allowable overload&#10;B)indication of materials used&#10;C)indication of efficiency&#10;D)way to identify a motor

Accepted Answer

The service factor of a motor is the allowable overload it can handle without overheating or degrading its expected life. It is a measure of the motor's ability to handle temporary overloads or demands beyond its rated horsepower. Therefore, choice A is the correct answer. The service factor of a general-purpose motor indicates the allowable overload that the motor can handle without causing damage. It is not an indication of the materials used, efficiency, or a way to identify the motor.

Question 7

Three-wire control prevents the restarting of machinery when power is restored.

Accepted Answer

Three-wire control ensures that a machine cannot restart automatically when power is restored, thus preventing any potential accidents or damage. It requires a manual reset by the operator to ensure safe operation. Three-wire control requires the operator to manually restart the machinery after power is restored, preventing automatic restarting and potentially dangerous situations.

Question 8

Line diagrams include all of the devices in the system and show the physical relationships between the devices.

Accepted Answer

Line diagrams, also known as schematic diagrams, focus on the function and flow of an electrical circuit, omitting the physical relationships and layouts of the devices.

Question 9

The control circuit consists of the main contacts and the overload heaters to the motor.

Accepted Answer

The control circuit typically includes components like relays, switches, and timers for controlling the motor, but not the main contacts and overload heaters, which are part of the power circuit.

Question 10

Two-wire control .&#10;A)provides no-voltage protection or low-voltage protection&#10;B)involves the use of a maintaining circuit&#10;C)prevents the restarting of machinery when power is restored&#10;D)provides no-voltage release or low-voltage release

Accepted Answer

Two-wire control typically involves the use of a control circuit that includes a no-voltage release or low-voltage release, which prevents the restarting of machinery when power is restored. It does not provide no-voltage protection or low-voltage protection, and does not involve a maintaining circuit. Two-wire control provides no-voltage release or low-voltage release, which means that the machinery will automatically shut off if there is a power failure or voltage drop. This is an important safety feature that can prevent accidents and damage to the equipment. Two-wire control does not provide no-voltage protection or low-voltage protection, nor does it involve the use of a maintaining circuit like three-wire control. However, it does prevent the automatic restarting of machinery when power is restored after a power failure, unless the operator manually resets the control.

Deck 5: Interpretation and Application of Simple Wiring and Elementary Diagrams