For example, 60 led lights are divided into 3 groups, and each group is 20 in series. When a certain led in a certain group burns out, all the leds in this group are not bright, but the led lights of other groups are still normally lit, the entire led light will be significantly dimmed due to the lack of a certain group of led lights for dimmable led power supply
2. The filter capacitor has deteriorated. The capacitor C2 led driver power supplycircuit is also a vulnerable component. long-term use of the capacitor will deteriorate, the capacity will become smaller, the filtering ability will be poor, and the poor filtering ability will cause the power supply voltage of the led lamp to be low, which will cause the led to dim.
2.The current-limiting resistor has deteriorated, its resistance value has increased or it has been blown. If the resistance of the current-limiting resistor becomes larger, the current of the led will become smaller, which will make the led dim.
4. The capacitance of the capacitive resistance step-down circuit has deteriorated. The capacitive resistance pressure circuit is composed of a capacitor and a resistor in parallel. The capacitive reactance of the capacitor is Xc= 1/2nfC, where n is a constant of about 3.14, f is the frequency of alternating current, the frequency of 220v alternating current is 50HZ, and c is the capacity of the capacitor. When the capacitance value of the capacitor becomes smaller, the capacitive reactance becomes larger, which causes the total impedance of the capacitive resistance circuit to become larger, so that the voltage drop becomes larger, and the voltage of the back-end led becomes lower, which makes the led dim.
5.If the led lamp is driven by a constant current source, it is also possible that the current sampling terminal of the constant current drive chip is faulty, which causes the current output of the constant current source to be low, thereby dimming the brightness of the LED.
6.The quality of the led lamp beads is not good, and the long-term work heat will cause the led light decay, thereby reducing the brightness. The led lamp bead has a long life, and the luminous efficiency of the led will be reduced after long-term operation, especially the poor heat dissipation makes theled transformer 12v 24v work in a hotter environment, and the quality of the l ed lamp is not good, and it will be used for a period of time.
