800Watt light-dimmer
This wide-range light dimmer circuit utilizes a unijunction transistor and a pulse transformer to implement phase control for the TRIAC. The circuit is designed to operate from a 115-volt, 60 Hz power source and can manage up to 800 watts of power for incandescent lighting. The control of the lighting power is achieved by adjusting the conduction angle of the TRIAC from 0° to approximately 170°. The power output at a 170° conduction angle is more than 97% of the power available at the maximum 180° conduction angle.
The light dimmer circuit employs a unijunction transistor (UJT) as a triggering device for the TRIAC, which is a semiconductor device capable of controlling large amounts of power. The UJT generates a pulse that is fed into the gate of the TRIAC, allowing it to conduct current. By varying the timing of this pulse, the phase angle at which the TRIAC begins to conduct can be adjusted. This is the essence of phase control, where the TRIAC is turned on at different points in the AC cycle, effectively controlling the power delivered to the load—in this case, incandescent lights.
The pulse transformer serves to isolate the control circuit from the high voltage AC line while also providing the necessary drive to the TRIAC. This transformer ensures that the UJT can safely operate at low voltage levels while still effectively triggering the TRIAC in the high voltage circuit. The design allows for a wide range of dimming capabilities, making it suitable for various lighting applications.
The circuit is powered by a standard 115-volt, 60 Hz AC supply, which is common in many residential and commercial environments. The ability to control up to 800 watts makes it versatile for different lighting setups, from small lamps to larger fixtures. The dimming range from 0° to 170° ensures that users can achieve a soft glow or full brightness, depending on their needs.
The efficiency of the circuit is highlighted by the fact that at a conduction angle of 170°, the power output is over 97% of that available at full conduction. This makes the circuit not only effective in controlling brightness but also energy-efficient, as it minimizes wasted power during operation. Overall, this light dimmer circuit represents an effective solution for adjustable lighting control in various settings.This wide-range light dimmer circuit uses a unijunction transistor and a pulse transformer to provide phase control for the TRIAC. The circuit operates from a 115 volt, 60 Hz source and can control up to 800 watts of power to incandescent lights.
The power to the lights is controlled by varying the conduction angle of the TRIAC from 0° to about 170°. The power available at 170° conduction is better than 97% of that at the full 180°. 🔗 External reference
The light dimmer circuit employs a unijunction transistor (UJT) as a triggering device for the TRIAC, which is a semiconductor device capable of controlling large amounts of power. The UJT generates a pulse that is fed into the gate of the TRIAC, allowing it to conduct current. By varying the timing of this pulse, the phase angle at which the TRIAC begins to conduct can be adjusted. This is the essence of phase control, where the TRIAC is turned on at different points in the AC cycle, effectively controlling the power delivered to the load—in this case, incandescent lights.
The pulse transformer serves to isolate the control circuit from the high voltage AC line while also providing the necessary drive to the TRIAC. This transformer ensures that the UJT can safely operate at low voltage levels while still effectively triggering the TRIAC in the high voltage circuit. The design allows for a wide range of dimming capabilities, making it suitable for various lighting applications.
The circuit is powered by a standard 115-volt, 60 Hz AC supply, which is common in many residential and commercial environments. The ability to control up to 800 watts makes it versatile for different lighting setups, from small lamps to larger fixtures. The dimming range from 0° to 170° ensures that users can achieve a soft glow or full brightness, depending on their needs.
The efficiency of the circuit is highlighted by the fact that at a conduction angle of 170°, the power output is over 97% of that available at full conduction. This makes the circuit not only effective in controlling brightness but also energy-efficient, as it minimizes wasted power during operation. Overall, this light dimmer circuit represents an effective solution for adjustable lighting control in various settings.This wide-range light dimmer circuit uses a unijunction transistor and a pulse transformer to provide phase control for the TRIAC. The circuit operates from a 115 volt, 60 Hz source and can control up to 800 watts of power to incandescent lights.
The power to the lights is controlled by varying the conduction angle of the TRIAC from 0° to about 170°. The power available at 170° conduction is better than 97% of that at the full 180°. 🔗 External reference
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