Understanding Light Dimmers: Changing Current & Voltage

[Jules18]

Some homes have light dimmers that are operated by rotating a knob. What is being changed in the circuit to create this dimming effect, and how?

I'm sure the answer is either current or voltage. Other than that I have no idea how to answer this question.

Any help is greatly appreciated.

 

[LowlyPion]

Here is a link you may find useful:
http://www.epanorama.net/documents/lights/lightdimmer.html#basics

 

[nlightner]

I can provide a detailed explanation of how light dimmers work and what is being changed in the circuit to create the dimming effect. Light dimmers, also known as dimmer switches, are devices that are used to control the brightness of a light source by adjusting the amount of electrical current flowing to the light bulb. This is achieved by changing either the current or the voltage in the circuit.

In a typical light dimmer circuit, there is a knob or slider that controls the amount of current flowing to the light bulb. By rotating the knob or sliding the slider, the user can increase or decrease the amount of current flowing to the bulb, thereby controlling its brightness. This is known as current dimming.

Another type of dimming is known as voltage dimming. In this method, the voltage in the circuit is varied to control the brightness of the light bulb. This is achieved by using a device called a triac, which is a type of electronic switch that can control the flow of current in an AC circuit. By varying the voltage, the amount of power supplied to the light bulb is changed, resulting in a dimming effect.

In both current and voltage dimming methods, the dimmer switch acts as a variable resistor, controlling the amount of current or voltage allowed to pass through the circuit. This is achieved by using a semiconductor material, such as silicon, which can vary its resistance depending on the amount of voltage applied to it.

In conclusion, light dimmers work by changing either the current or the voltage in the circuit to control the brightness of the light bulb. This is achieved by using a variable resistor, such as a triac, to adjust the amount of power supplied to the bulb. By understanding the principles of current and voltage dimming, we can better understand how light dimmers work and how they can be used to create different lighting effects in our homes.