How Do Dimmable LED Fixtures Work

Do LED Lights Need Special Dimmers?

Although LED lights are now dimmable, not all lights can be dimmed, and not all lights are dimmed in the same way. Due to the low power consumed by LEDs, many dimmers cannot work with LEDs in the same way as high power. When dimming the LED, you will notice:

**LED lights may not turn off at the lowest brightness, because the dimmer thinks that the LED lights are completely turned off, because the LED lights consume very little power.

**Smaller dimming range (usually 80-96%, CFL lamp is 0)

**On the dimming system based on DALI or DMX control technology, due to the small power fluctuations on the line, the LED may flicker during module communication.

It is recommended that you debug the current dimmer to see if it is compatible with your LED lights, it is possible that they can work normally, or the two are not compatible. However, if your current dimmer encounters any of the above-mentioned problems, it is recommended that you use 1-10V dimmers. These dimmers are currently the most widely used dimmers for LED lights on the market and provide a fine adjustment switch , It can realize comprehensive and intelligent control of dimming.

 

How Dimmable LED Fixtures Work

There are two main methods of LED dimming: DALI and DMX512. In DALI dimming, LED reflects the role of dimming by producing different luminous effects. Unlike lighting such as HPS, dimmable LED lights do not rely on voltage to determine their brightness. The difference is that they essentially depend on the cycle of opening and closing. These cycles take about a few milliseconds, so you won’t realize whether they are actually on or off. If you turn the lights to 25%, they will be “on” 25% of the time and “off” 75% of the time. For DMX, the process is simpler, where you can control the current to increase or decrease accordingly to dim or brighten the light.

• When is dimmable LED light worth using

All real estate agents say: “location, developer, floor”, this is not just for real estate. You must adopt a strategy where you install dimming LED lights. This is all about dimming purposes. If you want to illuminate the work area or the area that needs to be focused (such as a study desk), dimmable LEDs may not be very useful. In this case, we recommend that you use a non-dimmable cool white LED that emits a new light to help you see what you are doing and focus on the task at hand.

• Causes of dimmable LED lights strobe

Whether the dimmer switch is compatible with LED lights is the main cause of flicker. The LED dimmer switch has the smallest compatible load (that is, the number of watts it can load). The popular cutting-edge dimmer switch is mainly designed for older light bulbs with higher power, so the minimum load will be very high. In many cases, we will not be able to power low enough LED bulbs because they consume so little energy (and less electricity). This is why it is important to have a compatible LED dimmer switch to avoid any possible strobe. The quality of the dimmer switch also affects the performance of the lamp. High-quality dimmer switches will have different dimming modes and ranges. In most cases, just change the mode on the dimmer switch or reset the dimmer to its factory settings to correct the flickering dimmable LED.

• Reasons why dimmable LED lights are expensive

You may not understand why you have to invest more dollars for dimmable LED lights than non-dimmable ones, because dimmable LEDs have higher added value, increase manufacturing costs, and therefore increase the price (each bulb About US$0.5), so they are also more expensive than high-pressure sodium lamps or fluorescent bulbs. Because they have excellent technology and long-term profits. Compared with fluorescent lamps, they have the following advantages:

• 75% reduction in energy consumption-saving a lot of electricity bills,
• The service life is up to 10 times, so you don’t need to buy alternatives repeatedly,
• Smoother operation and quieter operation,

Therefore, when you use the dimmer switch to operate, you will no longer hear the buzzing sound, which is very common in traditional lights. Therefore, LED lights will save more money than non-dimmable lights in the long run.

• Installation of dimmable LED lights

First of all, before buying a transformer, make sure you know how many bulbs you want to power. There are a variety of power supplies for LED dimmable transformers. It is also important to remember that we recommend that the total power of all bulbs does not exceed 80% of the wattage of the transformer. For example, if you want to power 5 20W LED corn lights with a total power of 100W, you need a 125W transformer to generate enough power (and the subsequent 20% power loss). Second, we need to ensure that there are compatible dimmable switches. If you are upgrading from traditional sodium or fluorescent lamps to LED lamps, your current dimmer may not be compatible. Therefore, we recommend that you use a dedicated LED compatible dimmer switch to achieve flicker-free, quieter and smoother performance. If you use 12v LED lights, you need a dimmable transformer. The LED dimmable transformer allows constant voltage LED products to be dimmed and can be used with most standard dimmers, so you may not need to replace the existing dimmer switch.

How Does the Dimmer Switch Work?

How the current is limited to achieve control, it all comes down to the use of thyristors (transistor AC switches). TRIAC is a semiconductor device, a bit like a transistor composed of multiple layers of semiconductor materials, n-type (with free electrons) and p-type. A thyristor circuit has two terminals connected to both ends of the circuit, and the voltage difference changes with the fluctuation of alternating current. The upper and lower terminals are correspondingly switched between positively charged and negatively charged, and there is a gate connected to the circuit through a variable resistor.

In fact, TRIAC functions as a voltage-driven switch. The switching action is controlled by the voltage on the gate. The voltage on the gate is controlled by a variable resistor.

Since the voltage on the terminals is normal and the voltage on the gate is very low, the TRIAC is like an open-circuit switch and does not conduct electricity. If TRIAC is to conduct electricity between the two terminals, the voltage on the gate needs to be increased. When current passes through the resistor, the discharge capacitor is charged until it has enough voltage so that the current can be conducted to the lower terminal. The total resistance can be increased or decreased by moving the dimming knob, and the dimming knob will move the contact arm. When the dimming knob is dimmed, more resistance is provided, and turning the knob in the other direction reduces the resistance. When the current reaches zero voltage again, the cycle continues.

Although this method works well, the only real disadvantage is that the buzzing noise is very annoying for the dimmer. So, no matter what the changes are, the dimmer switches follow the same principle: they cut off the AC current, thereby reducing the total energy of the bulb.

The Specific Type of Dimmer Switch and How to Install the Dimmer Switch

Type of dimmer switch

• Unipolar: Unipolar is specially designed for a fixture controlled by a dimmer. This means that the dimmer will act as the only switch that can either turn the lights on or off, or dim them.

**3-way or 4-way: If there are multiple switches for lighting, a 3-way or 4-way dimmer is required

• Multi-position: Multi-mate dimmers require multi-position dimmer switches, allowing full control of brightness in multiple positions

**Plug-in type: Table lamps and floor lamps require a plug-in dimmer.

The advantage of using a dimmer switch is to change the lighting of a room for multiple purposes.

How to install the dimmer switch

In the living room, you can lower the lights to create an atmosphere of intimate entertainment with guests, and then turn the lights up when you need a little brightness to play board games with the children.

When it’s time for the children to sleep, you can dim the lights in their room and let them slowly fall asleep. In the morning, you can ensure that there is enough light to start the day energetically.

When you want to relax in the bathtub in the bathroom, use a dim light. When you need to shave or make up, increase the brightness of the light.

In addition to mood lighting, it can also save electricity bills. Dimming the lights by 25% can save 20%, while dimming the lights by half can reduce consumption by 40%. It is worthwhile month after month. Since the pressure on the bulb is less, the service life of the bulb can be extended.