Question 1

Float switches are rotary, manual switching devices that are often used to reverse motors and to control the speed of&#10;AC and DC motors.

Accepted Answer

Float switches are actually not rotary switches, but rather a type of switch that detects fluid levels and triggers a circuit to turn pumps or other devices on or off. They are not typically used for motor control. Float switches are typically used in liquid or fluid applications to detect the level of the fluid and turn on or off a pump or motor as needed. They are not typically used for reversing motors or controlling motor speed.

Question 2

are used most frequently as overtravel stops for machines, equipment, and products in process.&#10;A)Thermostats&#10;B)Float switches&#10;C)Pressure switches&#10;D)Limit switches

Accepted Answer

Limit switches are specifically designed to control the movement of machinery by stopping it when the limit of travel has been reached. They are widely used as overtravel stops for machines, equipment, and products in process. Thermostats, float switches, and pressure switches are not designed for this purpose. Limit switches are specifically designed to be used as overtravel stops and are the most commonly utilized type of switch for this purpose. Thermostats, float switches, and pressure switches are typically used for other applications such as temperature control, liquid level sensing, and pressure monitoring, respectively.

Question 3

A manual control is one whose operation is accomplished by mechanical means.

Accepted Answer

A manual control is operated by using physical methods such as turning a knob or flipping a switch, as opposed to electronic controls which rely on electronic signals to execute commands. A manual control is operated by physical movement or mechanical means, such as pushing a button or turning a dial.

Question 4

Air compressors are started directly or indirectly on a call for more air by a .&#10;A)thermostat&#10;B)float switch&#10;C)pressure switch&#10;D)limit switch

Accepted Answer

Air compressors are typically started on a call for more air by a pressure switch, which monitors the air pressure in the tank and turns the compressor on or off accordingly. A thermostat is used to regulate temperature, a float switch is used in liquid applications, and a limit switch is used to control the movement of equipment. Air compressors are typically started on a call for more air by a pressure switch, which senses the pressure in the tank and signals the compressor to turn on or off accordingly. A thermostat is used to control temperature, a float switch is used to control liquid levels, and a limit switch is used to control machinery movement. None of these switches are specifically related to starting an air compressor.

Question 5

Current-limiting acceleration is also called .&#10;A)compensating time&#10;B)acc time&#10;C)delay time&#10;D)limiting time

Accepted Answer

Current-limiting acceleration is also called compensating time because it is the time it takes for the current-limiting device to operate and limit the current.

Question 6

A varying speed is usually preferred for .&#10;A)water pumps&#10;B)cranes and hoists&#10;C)turret lathes&#10;D)paper and printing plants

Accepted Answer

Cranes and hoists often need to operate at varying speeds in order to precisely move and position heavy loads. Cranes and hoists typically need to vary their speed to adjust for heavier or lighter loads, as well as to maneuver safely and efficiently in different settings. The other options may not necessarily require varying speeds.

Question 7

The fundamental tasks of a motor controller are to start and stop the motor and to protect the motor, machine, product, and .&#10;A)instruments&#10;B)pipes&#10;C)plant&#10;D)operator

Accepted Answer

The motor controller is responsible for protecting the operator from any danger related to the operation of the motor. It can detect unsafe conditions such as overloads, short circuits, over-temperature, and ground faults, and take action to prevent harm to the operator or damage to the equipment. Therefore, protecting the operator is one of the fundamental tasks of the motor controller. The motor controller's main task is to protect the operator from harm by controlling the motor in a safe and reliable manner. It also starts and stops the motor and protects the machine, product, and plant by ensuring that the motor is running at the optimal settings. Therefore, the best choice is D- operator.

Question 8

Automatic stopping devices greatly reduce the safety hazards of operating some types of machinery.

Accepted Answer

Automatic stopping devices, such as emergency stops or automatic shut-offs, can quickly and automatically stop machinery in dangerous situations, reducing the risk of accidents and injuries. Automatic stopping devices can help prevent accidents by automatically stopping the machinery if there is an issue or danger present. This reduces the risk of injury to the operator and other workers.

Question 9

The common function of all controls is to control the operation of an electric motor.

Accepted Answer

The statement is true. The primary function of electric motor controls is to regulate the operation of an electric motor.

Question 10

Equipment that is tested and approved by UL is listed in a publication that is updated every two years.

Accepted Answer

UL (Underwriters Laboratories) updates its certification directory continuously online, allowing for real-time access to the latest information on equipment and products that have been tested and certified.

Deck 1: General Principles of Electric Motor Control