LED spot light is broken and not bright, how to flicker?

Nowadays, when many people install lamps in their homes, in addition to the lamps used for lighting, they will also install some spotlights, such as the spotlights installed on the ceiling of the TV wall. Then, if the bulb is broken, the LED spotlights are broken and not bright, how to shine?

In fact, the replacement of the spot light bulb is not very difficult, as long as it is found the right way, then it is very simple to replace the bulb of the spot light, there is no need to ask a professional master to repair, money and time consuming.

First of all, let‘s turn off the switch of the spot light to ensure the safety of replacement, and then use a flat-head screwdriver to pry up the outer ring. The whole light can be removed. After changing the bulb, tilt the first side and then push the whole light flat.

Take down the spotlights can find sales manufacturers after-sales service, general LED product warranty is at least two years.

Analyze the problem

3W MR16 LED(12V(stabilized voltage input) spotlights and switching power supply (12V/2.5A), each switching power supply with 6~8pcs of different spotlights, but after half a year of use, several groups of LED spotlights show shining phenomenon, sometimes, all switching power supply is hot (more than 60 degrees), switching power supply placed on the flowering, ventilation is also able, When the voltage and current are tested, the output and input are normal. When the LED shines, the switching power supply has no output current.

Analysis of possible causes

LED low-voltage spot lamp refers to the lamp whose driver device is directly connected to the halogen lamp electronic transformer in the M16 and M11 lamp cups. Because the electronic transformer is planned for the halogen lamp, it is not suitable to be used as the power source of the LED driver. When three leds are connected in series to the halogen lamp transformer, there will be two problems, such as spot failure and low-frequency shining. The rated voltage of the low-voltage halogen lamp is 12V. In order to extend the service life of the halogen lamp, the output voltage of the electronic transformer is intentionally planned to be slightly lower than the rated voltage of the halogen lamp, generally 11.3 ~ 11.5V. The usual low pressure LED driver is Buck construction, which requires a differential pressure of at least 0.3V for normal operation, i.e. VBuck = 0.3V. If the PN junction positive voltage of the LED is 3.4V, the sum of the positive voltage VF of the three leds is 10.2V. The full bridge pressure drop of Schottky is about 1V, namely VD = 1V. When the input voltage VIN-(VD + VF) < VBuck, the driver will not work properly and the LED will not light up. As shown in Figure 1, after the three leds are connected to the electronic transformer with an output voltage of 11.3V through the Buck driver, the output voltage of the driver is only 10V, which is less than the on-off voltage of the three leds in series, so the LED is not bright.

How to choose spotlights

Spotlights are divided into low pressure and high pressure. Customers are better to choose low pressure spotlights, which have longer life and higher light efficiency. The higher the power factor, the better the light effect. The power factor of the ordinary spot lamp is about 0.5, and the price is cheap. The power factor of the high-quality spot lamp can reach 0.99, and the price is a little more expensive. Spotlights are generally used to enhance the lighting of decorative objects, usually embedded in the ceiling or wall. Spotlights generally emit high temperatures when working, so we must buy high-quality products, otherwise there will be safety risks. When the spot lamp is used, the transformer should be deployed. The lamp beads should also be of good quality. Otherwise, the lamp beads of the spot lamp are easy to be broken. And now the quality of spotlights on the market is uneven, it is difficult to distinguish good from bad with the naked eye, so it is better to buy spotlights to choose brand products, and select high-quality transformers.