Common dimming methods of LED lights

LED era is developing rapidly, the control of lamps and lanterns is no longer simply open and close, a variety of dimming methods have been used in a variety of shopping malls, hotels, office buildings to meet the needs of different times, different scenes on the light environment.

At present, intelligent control of dimming methods are mainly the following.

A, cutting-edge phase control dimming

The principle is to adjust the conduction angle of each half wave of AC power to change the sinusoidal waveform, thereby changing the effective value of AC current, so as to achieve the purpose of dimming. Frontier dimming as the market leading dimming method has the advantages of high accuracy, small size, light weight, easy to manipulate from a distance, most manufacturers of products are this type of dimmers. Frontier phase control dimmers generally use silicon controlled as a switching device, so also known as silicon controlled dimmers.

The advantages of silicon controlled dimmers are: low cost of dimming, compatible with existing lines, no rewiring along the back of the cut phase control dimming. The disadvantage is that the poor dimming performance of silicon thyristor, usually resulting in a reduced dimming range, and can lead to the minimum required load are more than a single or a small number of LED lighting power rating. Because of the properties of the SCR semi-controlled switch, only the function of turning on the current, and can not completely turn off the current, even if adjusted to the lowest still have a weak current through, and LED micro-current light characteristics, so that a large number of dimming with SCR off the existence of LED still have a weak light phenomenon exists.

Second, the back edge of the tangential control dimming

The principle of the trailing edge tangential dimmer is that the half wave of the AC voltage immediately after the start of the on, when the half wave voltage reaches the set on angle immediately off, by adjusting the on angle to achieve dimming purposes.

Rear-edge tangential dimmer generally uses MOSFET as a switching device, consisting of a rear-edge phase controller, active switch, over-zero detection circuit and overload protection circuit, it is not only able to dimmable incandescent lamps, but also has a good adaptability to electronic voltage loads, in most cases can work well.

Compared with the former tangential phase dimmer, the rear edge tangential dimming due to no minimum maintenance current requirements, while solving the problem of grid interference and noise, theoretically better matching, but the internal circuit structure is more complex, the control cost is relatively high.

Third, 0/1-10V dimming

0-10V dimming is also called 0-10V signal dimming, is an analog dimming method. The difference between the SCR dimming power supply is 0-10V power supply with two more 0-10V interface (+10V and -10V), it is by changing the voltage of 0-10V to control the output current of the power supply to achieve dimming. 10V when the brightest, 0V when off. And 1-10V just dimmers are 1-10V, when the resistor dimmer is adjusted to a minimum of 1V, the output current is 10%, if the output current is 100% at 10V, the brightness will also be 100%. It is worth noting that it is also best to distinguish that 1-10V does not have the function of a switch, can not be adjusted to the minimum to turn off the role of the lamps, while 0-10V has the function of a switch.

Simply put a room with many lights, to each light with 0/1-10V control line, and connected to the controller. When the controller is adjusted, the voltage on the control line changes, and the lights are dimmed or brightened.

The disadvantage of 0/1-10V dimming is: a controller corresponding to multiple groups of lamps can only change at the same time, if you want to achieve different control of each lamp, then only let the controller and lamps one by one, when the number of lamps up, the operation will become very troublesome.

Fourth, DALI dimming

DALI (Digital Addressable Lighting Interface) is the international public specifications of the lighting control communication protocol. dali system is suitable for scene control, light source fault state feedback. dali system gives new meaning to the lamps and lanterns, each lamp has an independent address, dali system on the light source and lamps and lanterns do not require, but require ballasts, drivers and other components to meet the dali standard, the address of the lamps and lanterns by their embodiment.

The four letters DALI each mean: Digital Digital Addressable Addressable Lighting Lighting Interface interface. dali can be dimmable for each luminaire with DALI driver, different lighting units on the DALI bus can be flexibly grouped to achieve different scenes control and management. Compared to other dimming methods, DALI dimming advantages are: 1, digital dimming, dimming accurate and stable smooth; 2, DALI can be two-way communication, you can feedback to the system of the lamps; 3, DALI control more flexible; 4, DALI anti-interference ability.

Five, wireless control dimming

Wireless control dimming refers to the WIFI, Bluetooth controller and other ways to adjust the light and darkness of each group of lamps and lanterns, open and close, so as to change the light environment to form a variety of lighting scenes. Compared to other dimming methods are more simple and convenient, users can use cell phones, Bluetooth panel switch, smart speakers to adjust the light environment; disadvantage is that the coverage is small, control the number of lamps and lanterns is less, so more suitable for home furnishings, villas such as a small range of space use.