Summary of Wie funktioniert ein Potentiometer? Aufbau und Funktionsweise | Elektronik #5
Summary of "Wie funktioniert ein Potentiometer? Aufbau und Funktionsweise | Elektronik #5"
This video explains the construction, working principle, and practical use of a Potentiometer, a common and useful electronic component.
Main Ideas and Concepts
- What is a Potentiometer?
- A Potentiometer is a passive, mechanical Variable resistor.
- Unlike semiconductor components (diodes, transistors), it is made with mechanical parts.
- It has a sliding contact (Wiper) that allows adjustment of resistance.
- Used to generate a variable voltage output.
- Commonly seen as rotary knobs on devices like stereo systems.
- Physical Construction
- Typically has three electrical connections (pins):
- Pins 1 and 3 connect to a fixed Resistive element (resistance material).
- Pin 2 is connected to the Wiper, which slides along the Resistive element.
- Some potentiometers may have four pins, but two are internally connected, effectively making three connections.
- The Resistive element forms a fixed resistance between pins 1 and 3 (e.g., 100 ohms, 2.2 kilo-ohms).
- Typically has three electrical connections (pins):
- How It Works
- The Wiper (pin 2) moves along the resistive track when the knob is turned.
- This changes the resistance between pin 2 and pins 1 or 3.
- Resistance between pin 2 and one end varies from near 0 ohms (Wiper close to that pin) up to the full resistance value (Wiper at the opposite end).
- This variable resistance allows for adjusting voltage output from the Potentiometer.
- Practical Demonstration
- Using a Multimeter, the resistance between pins 1 and 3 is constant.
- Resistance between pin 2 and pin 1 or pin 3 changes as the knob is turned.
- Example measurements:
- Electrical Model and Voltage Division
- The Potentiometer can be modeled as two resistors in series, with the Wiper as the junction.
- Total resistance is fixed (R_fixed).
- When a voltage (e.g., 10V) is applied across pins 1 and 3, the voltage at pin 2 depends on the position of the Wiper.
- The voltage divides proportionally according to the resistance values on either side of the Wiper.
- This creates an adjustable Voltage divider, useful for tuning or controlling circuits.
- Applications
- Potentiometers are used to adjust settings in electronic devices.
- The video hints at practical use with Arduino in a follow-up video.
Methodology / Instructions for Testing a Potentiometer
- Identify the three pins: 1, 2 (Wiper), and 3.
- Measure resistance between pins 1 and 3 to find total resistance.
- Connect a Multimeter between pin 2 and pin 1.
- Rotate the Potentiometer knob:
- Observe resistance changes from near 0 to maximum resistance.
- Repeat measurement between pin 2 and pin 3.
- Understand that the Wiper divides the total resistance into two variable parts.
- Use the Potentiometer as a Voltage divider by applying voltage across pins 1 and 3 and measuring voltage at pin 2.
Speakers / Sources
- Primary Speaker / Presenter: Unnamed instructor explaining electronics concepts in German.
- No other speakers or external sources explicitly mentioned.
This summary captures the essential educational content on potentiometers from the video, including theory, construction, practical testing, and applications.
Notable Quotes
— 04:05 — « You may already have guessed what that means. Using this mechanism, a variable resistance can be set between the middle pin 2 and the two outer pins. »
— 07:38 — « This is exactly the functional principle that you have a potentiometer can generate an adjustable voltage. »
— 07:51 — « If you don't want to miss it then best leave a subscription and click once on the bell. »
Category
Educational