What is Potentiometer? What is potentiometer used for?

In the field of electronics, potentiometers are an important and popular component, widely used in signal and voltage regulators. In this article, RX Tradex will help businesses better understand what is potentiometer, its structure, uses, and how to measure and connect potentiometers effectively.

1. What is potentiometer?

A potentiometer, also known as a potentiometer, is an electronic component that regulates the voltage in electrical circuits, which has at least one mobile contact, allowing the user to adjust the value of the resistance and thereby regulate the distribution voltage.

Potentiometers work by dividing the electricity into parts with variable values, which in turn allows the voltage at the mobile contact to be adjusted, in proportion to the value of the resistance. In many electrical and electronic devices, potentiometers are used to regulate signal levels or electrical strength. Although in many applications, the power dissipated on potentiometers is only small, in some cases, it can be up to a few watts or even hundreds of watts.

2. Structure of potentiometers

Potentiometers usually come in a variety of shapes and sizes, but the principle of operation and basic construction are the same. Here are the 6 basic components that make up potentiometers:

• Potentiometer Body: Usually made of plastic or metal, the potentiometer body contains the entire internal components and provides a sturdy frame for the device.
• Adjustable Shaft: This is the part that the user can rotate to change the resistance value. This shaft connects to the lever and allows the sliding contact to be moved on the resistance surface.
• Surface Resistance: This is a fixed strip of resistance, usually made of charcoal, cermet (a ceramic and metal compound), or winding wire, which is installed inside a potentiometer. The value of the resistance will vary based on the position of the sliding contact on this band.
• Sliding contact (Wiper): This is the mobile contact attached to the adjustment shaft. When the shaft is rotated, the sliding contact moves along the resistance surface, creating a change in the resistance value and output voltage.
• Connection pins: Potentiometers typically have three connection pins. The outermost two pins connect to the two ends of the resistive surface, the middle pin (wiper pin) connects to the sliding contact. The resistance value between the middle leg and each outer leg will change as the shaft rotates.
• Lever: Attached to the adjustable shaft and helps to move the sliding contact when there is a change in the angle of the shaft.

3. What are the uses of potentiometers?

Potentiometers are widely used in power amplification and sound processing systems, such as amplifiers, mixers, thrusters, digital reverbs, and many other devices. They are usually integrated directly into the audio device’s circuitry or used as a standalone device to flexibly adjust the volume and sound quality.

4. How many types of potentiometers are there?

In fact, potentiometers come in many types and are classified based on different characteristics. However, in the technical field, potentiometers are generally divided into two common types: 3-pin potentiometers and 6-pin potentiometers.

1. 3-pin potentiometer

The 3-pin potentiometer is the simplest and most common type. Often designed as a Dimmer, they are primarily used in residential electrical appliances. The structure of a 3-pin potentiometer consists of three main parts: a wiper, a large coil of resistance made of alloy, and three pins connected to the circuit. In addition, this potentiometer has a dial that helps regulate the resistance, thereby controlling electrical devices.

2. 6-pin potentiometer

Although not as popular as 3-pin potentiometers, 6-pin potentiometers still play an important role in many devices, especially in audio systems. This type of potentiometer has 6 contacts for receiving and transmitting signals, and is divided into two main forms: a twin-pin 6-pin potentiometer (2-stage) and a 1-stage 6-pin potentiometer.

• Double 6-pin potentiometer: This type works similarly to a 3-pin potentiometer, but instead of needing to use two separate 3-pin potentiometers, one can replace it with a double 6-pin potentiometer to save space and components. Each stage in this potentiometer will connect to an audio channel (left and right), which helps to synchronously adjust both speakers with a single button twist.
• 6-pin 1-stage potentiometer: More complex operation, this type allows up to four devices to adjust and transmit a fixed signal to another, often used in applications that require flexible and precise adjustment.

The variety of potentiometers makes them suitable for a variety of applications, from simple devices such as fans and lights, to complex systems such as audio and controls.

5. How to measure standard potentiometer

The specifications of electronic components, including potentiometers, are usually written directly on the device by the manufacturer. However, to check if the potentiometer is still working well, we can measure its value ourselves. Although the results may vary slightly due to the current factor, this method still allows us to accurately assess the potentiometer’s operability.

Steps to measure potentiometer:

• Prepare the device: Use a multimeter and set the scale of the meter to a level higher than the maximum resistance value of the potentiometer.
• Connect the measuring jack: Attach the black jack to the negative terminal and the red jack to the positive terminal of the multimeter.
• Take measurements:

o   Set the potentiometer knob to the minimum position (left drama).

o   Attach the probe to the two ends of the potentiometer.

o   Slowly turn the potentiometer knob towards the maximum (drama right) and observe the change in the resistance value on the watch.

o   This operation can be repeated in the opposite direction.

• Summarize the results: Repeat the measurement process several times, record the results, and calculate the average value. If this value is close to the reading on the potentiometer, the device will still operate normally. If the value deviates a lot, it is possible that the potentiometer is broken or the measurement is not standard.

Some notes when measuring potentiometer:

• Make sure the circuit is free of power: Before proceeding with the measurement, make sure the potentiometer is disconnected from the power supply to avoid danger and misalignment of the results.
• Avoid direct contact: Do not allow your hands to touch both the probe and the potentiometer foot at the same time as this may cause interference and make the results inaccurate.

The potentiometer measurement is quite simple, but for high accuracy, we should do it several times and compare the results. If the measured average value is close to the standard value from the manufacturer, the potentiometer is still in good use. If the results deviate significantly, potentiometer replacement may be considered to ensure the performance of the device.

6. How to match the ceiling fan potentiometer

The connection of ceiling fan potentiometers is not too complicated, you can refer to the diagram below to do it:

Looking at the diagram, businesses will see that the potentiometer connection for ceiling fans is simpler than audio equipment. With just a few basic steps, we can complete the potentiometer installation in a short time. However, it is necessary to pay attention to ensure the correct polarity and potentiometric feet. The color symbols on the wires will help businesses recognize and connect accurately, with wires of similar colors connected to each other.

7. Conclusion

Hopefully, the above article has helped businesses have an overview of “what is potentiometer”, as well as how to use them effectively. In addition, if you are operating in the electronics sector and want to stay up-to-date with the latest technology trends, don’t miss NEPCON Vietnam 2024 – the largest and only electronic  exhibition on SMT, Inspection Technology, Equipment and Supporting Industries for Electronics Manufacturing in Vietnam organized by RX Tradex Vietnam,  will take place from 11-13/09 at the Viet-Soviet Friendship Palace (I.C.E), Hanoi. This is an opportunity for businesses to meet partners, explore advanced solutions in the field of electronics industry and expand business networks. Register now for exhibitors or visitors.