Dim lighting. How do dimmers function?

You can adjust the amount of power, voltage, or current that is sent to a device with a dimmer, which lowers or raises the temperature at which an iron, electric heater, electric stove, or soldering iron heats.

The term “dimmer” relates to the device’s frequent use in adjusting light brightness. You can use dimmers to save energy, lengthen the life of your bulbs, accurately adjust the brightness of the light source, and create a range of lighting effects. Because the eye can adapt more readily to a steady decrease in brightness, the dimmer also reduces eye strain.

The functioning principle of the dimmer

The early dimmers used a variable resistor to adjust the light level. Ordinary resistors offer a large amount of resistance to an electric charge in motion because they are constructed from materials that conduct electricity inefficiently. Resistant refers to a substance with certain characteristics. A variable resistor is made of a resistive component, a fixed contact arm, and a movable contact arm. By altering the distance the charge must travel through the resistive material, the resistor’s overall resistance can be altered.

If the contact arm is on the left, the charge moving through the circuit only needs to pass through a small amount of resistance. If the contact lever is fully to the right, the charge must pass through the entire resistive material, increasing the resistance of the resistor. When a resistor is charged, the energy is released as heat. Because of the resistor’s power consumption, a series circuit loses voltage when a resistor is added, which reduces the amount of power available to another load (such as a light bulb). If the voltage is decreased, the light bulb’s brightness will be reduced.

In this dimming technique, the variable resistor, which also acts as a voltage divider, wastes energy as heat. Such switches are not only cumbersome and occasionally dangerous, but also useless because the resistor generates a lot of heat. Modern dimmer switches use a more successful approach. Instead of sending current from a light bulb to a resistor, modern resistors quickly turn power on and off to reduce the overall amount of current flowing through the circuit. Each second, the circuit for the light bulbs shuts down many times.

The switching cycle is built on fluctuations in alternating current. Due to the alternating voltage polarity of alternating current, it oscillates in an undulating sine wave from a positive voltage to a negative voltage. In other words, the direction of the traveling charge in an alternating current is continually changing. An advanced dimmer “cuts” a sine wave. The light bulb circuit is quickly turned off whenever the current changes or when there is no voltage present in the circuit. This happens twice per cycle, or 120 times per second. The light circuit is turned back on when the voltage reaches the predetermined level once more.

This “on value” is determined by the position of the brightness control knob or slider. If the dimmer is set to a brighter setting, the light will turn on instantly after being turned off. The light bulb receives more electricity every second since the circuit is running for the majority of the cycle. If the dimmer is set to a dimmer light, the light will delay turning on until a later turn in the cycle.

Because they are more effective, modern dimmers are made of semiconductors rather than variable resistors. In comparison to a variable resistor, solid state or solid state dimmers dissipate extremely little power since they swiftly switch between a low resistance “on” state and a high resistance “off” state.

These are the fundamental ideas behind a dimmer’s operation. Modern professional dimmers have a more sophisticated component. Typically, a digital control system like DMX or DALI is used to manage them. These protocols are frequently used in conjunction with Ethernet in more recent systems.