The Construction Of An Across The Line Starter Includes:Select One:A. Three-phase Contacts And A 120-volt CoilB. Contacts To Close The Motor Circuit And Overloads To Protect The MotorC. A Set Of Three-phase Contacts And In-line FusesD. A Three-phase

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**The Construction of an Across-the-Line Starter: A Comprehensive Guide**

What is an Across-the-Line Starter?

An across-the-line starter, also known as a direct-on-line (DOL) starter, is a type of motor starter that connects the motor directly to the power supply. It is the simplest and most common type of starter used in industrial applications.

The Construction of an Across-the-Line Starter

The construction of an across-the-line starter includes:

  • Three-phase contacts and a 120-volt coil: This is the correct answer. An across-the-line starter consists of three-phase contacts that connect the motor to the power supply, and a 120-volt coil that controls the operation of the starter.
  • Contacts to close the motor circuit and overloads to protect the motor: While this is a feature of some motor starters, it is not the correct answer for an across-the-line starter.
  • A set of three-phase contacts and in-line fuses: This is not the correct answer, as in-line fuses are not typically used in across-the-line starters.
  • A three-phase: This is not a complete answer, as an across-the-line starter requires more components than just a three-phase configuration.

How Does an Across-the-Line Starter Work?

An across-the-line starter works by connecting the motor directly to the power supply when the starter is energized. The starter consists of three-phase contacts that connect the motor to the power supply, and a 120-volt coil that controls the operation of the starter.

When the starter is energized, the 120-volt coil is activated, which in turn closes the three-phase contacts, connecting the motor to the power supply. The motor then starts to rotate, and the starter remains in the "on" position until the motor is stopped.

Types of Across-the-Line Starters

There are several types of across-the-line starters, including:

  • Manual starters: These are the simplest type of starter and are operated manually by a switch or button.
  • Automatic starters: These starters are operated automatically by a timer or other control device.
  • Soft-start starters: These starters use a soft-starting technique to reduce the inrush current of the motor.
  • Reduced-voltage starters: These starters use a reduced-voltage technique to reduce the inrush current of the motor.

Advantages and Disadvantages of Across-the-Line Starters

Advantages:

  • Simple design: Across-the-line starters have a simple design that makes them easy to install and maintain.
  • Low cost: Across-the-line starters are generally less expensive than other types of starters.
  • High reliability: Across-the-line starters are highly reliable and have a long lifespan.

Disadvantages:

  • High inrush current: Across-the-line starters can cause a high inrush current when the motor is started, which can lead to voltage drops and other problems.
  • Limited control: Across-the-line starters do not offer much control over the motor, as the motor is connected directly to the power supply.
  • Not suitable for all applications: Across-the-line starters are not suitable for all applications, as they can cause problems with voltage drops and other issues.

Applications of Across-the-Line Starters

Across-the-line starters are commonly used in a variety of applications, including:

  • Industrial applications: Across-the-line starters are widely used in industrial applications, such as in factories and manufacturing plants.
  • Commercial applications: Across-the-line starters are also used in commercial applications, such as in office buildings and shopping centers.
  • Residential applications: Across-the-line starters are used in residential applications, such as in homes and apartments.

Conclusion

In conclusion, an across-the-line starter is a type of motor starter that connects the motor directly to the power supply. It is the simplest and most common type of starter used in industrial applications. While it has several advantages, including a simple design and low cost, it also has several disadvantages, including high inrush current and limited control. Across-the-line starters are commonly used in a variety of applications, including industrial, commercial, and residential applications.

Frequently Asked Questions

Q: What is the difference between an across-the-line starter and a soft-start starter?

A: An across-the-line starter connects the motor directly to the power supply, while a soft-start starter uses a soft-starting technique to reduce the inrush current of the motor.

Q: What are the advantages of using an across-the-line starter?

A: The advantages of using an across-the-line starter include a simple design, low cost, and high reliability.

Q: What are the disadvantages of using an across-the-line starter?

A: The disadvantages of using an across-the-line starter include high inrush current, limited control, and not being suitable for all applications.

Q: What are some common applications of across-the-line starters?

A: Some common applications of across-the-line starters include industrial applications, commercial applications, and residential applications.

Q: How does an across-the-line starter work?

A: An across-the-line starter works by connecting the motor directly to the power supply when the starter is energized. The starter consists of three-phase contacts that connect the motor to the power supply, and a 120-volt coil that controls the operation of the starter.