What is a Variable Resistor?

Master Electrician
07/12/2024


What is a Variable  Resistor?


Variable resistor definition


 Resistor whose resistance can be adjusted as needed. It is a common component in electronic circuits that allows current or voltage to be adjusted according to Ohm's law.


Basic structure of variable resistor


A variable resistor usually has three terminals: two fixed terminals at the end of the resistance track and one removable terminal (cursor). Depending on how the terminals are connected to the circuit, a variable resistor can be used as a rheostat or potentiometer.


屏幕截图 2024-07-12 095947_修复后.png


Variable resistor working principle


A variable resistor works by changing the length of its resistance track. Moving the wiper contacts along the track adjusts the resistance between the terminals.


Variable resistor operating characteristics


  • Resistance range: Minimum and maximum possible resistance values

  • Linearity: Indicates the proportional change in resistance with the cursor position.




Applications of variable resistors


  • Audio control: Variable resistors can be used to adjust the volume, tone, bass and treble of sound systems, radios, headphones, speakers, etc.

  • Television: Variable resistors can be used to adjust the color, brightness, contrast, and position of images on the TV screen.

  • Motion control: Variable resistors can be used to control the speed, direction and torque of motors, steering engines, fans, pumps, etc. They are usually connected as rheostat to change the current passing through the load.


Master Electrician

We aim to gather electrical knowledge and share it with others.

Battery charging process using AC adapter
Battery charging process using AC adapter
The process of charging the battery using the AC adapter is as followsConnecting devicePlug the AC adapter into the power outlet, making sure the connection is secure and stable. At this point, the AC adapter starts to obtain AC power from the grid.Connect the output of the AC adapter to the device that needs to be charged, usually through a specific charging interface or data cable.Ac adapter operationInput AC conversionThe circuit inside the AC adapter first rectifies the input AC power, conve
Encyclopedia
09/25/2024
The circuit working principle of one-way switch
The circuit working principle of one-way switch
A one-way switch is the most basic type of switch that has only one input (often called the "normally on" or "normally closed" state) and one output. The working principle of the one-way switch is relatively simple, but it has a wide range of applications in various electrical and electronic devices. The following details the circuit working principle of the one-way switch:The basic structure of a one-way switchA one-way switch usually consists of the following parts: Contact: A metal part used
Encyclopedia
09/24/2024
What is electrical knowledge?
What is electrical knowledge?
Electrical knowledge covers a broad set of theoretical and practical skills related to the basic principles of electricity, circuit design, operation and maintenance of power systems, and the working principles of electronic devices. Electrical knowledge is not limited to academic theory, but also includes skills and experience in practical applications. Here is an overview of some of the core areas of electrical knowledge:Basic concept Circuit theory: includes the basic components of the circui
Encyclopedia
09/24/2024
What is the effect of applying alternating current to a DC machine?
What is the effect of applying alternating current to a DC machine?
Applying alternating current to a DC motor can have a variety of adverse effects because DC motors are designed and operate to handle direct current. The following are the possible effects of applying AC to a DC motor:Cannot start and run properly No natural zero crossing: AC has no natural zero crossing to help the motor start, while DC motors rely on constant direct current to establish a magnetic field and start. Inversion phenomenon: The sinusoidal waveform of alternating current changes dir
Encyclopedia
09/24/2024
Inquiry
Download
IEE-Business is dedicated to serving the personnel in the global power industry.
Join IEE-Business, not only can you discover power equipment and power knowledge, but also canhnd like - minded friends!