Adjustable resistors, also known as potentiometers, allow a degree of control over the resistance within a circuit. This gives them an advantage over other types of fixed resistor, depending on your needs.
They are composed of a fixed resistive element, and a slider that is able to pass along the element. This is what changes the resistance of the circuit, and it is usually controlled externally.
What are adjustable resistors used for?
Adjustable resistors are most commonly used for volume control in TV and radio. They can also be used as part of a light dimmer, to indirectly affect the level of light.
Types of adjustable resistor
Adjustable resistors largely vary based on material
- Wirewound adjustable resistors use a coil of resistance wire, and offer the highest performance.
- Cermet adjustable resistors are composed of ceramic and metal. They can withstand high temperatures, and are often used in trimmer resistors.
- Carbon composition adjustable resistors are some of the most common types used, as they are a good all-purpose resistor.
- Conductive plastic adjustable resistors use conductive plastic ink, and have a low noise output.