LED lights have brought us a lot of convenience, I can't say enough -- they're a huge part of what makes today's nightlife so colorful. But leds have their own drawback, the "glass heart" -- they are much more sensitive to current than incandescent and fluorescent bulbs. Thus if something goes wrong, it will show you by flashing and shimmering after the lights are off -- flashing and shimmering are the same kind of fault, both cause and solution are the same, so they can be regarded as equivalent. (In order not to be wordy, this fault is referred to as "flickering.")
The causes of LED flashing after the switch is off cannot be determined, you need to rule them out one by one. There are three possibilities that may cause the LED light to blink after the switch is off: 1. 2. The lamp generates a self-inductive current; 3. the current is still running after the switch is off. The following led addressable strip lights respectively to describe the characteristics of various reasons and solutions.
The switch controls the neutral line
Switch control zero, lighting circuit wiring is a huge taboo, but also numerous non-professional electricians make the most easy mistakes. In the imagination of ordinary people, a neutral wire and a live wire can be used to light an electric lamp.
Figure 1
But have you ever wondered what would happen if the zero and fire lines were reversed? Like this ▼
Figure 2
In the two graphs above, the difference between the neutral line and the live line is completely illustrated. The live line invariably has a peak potential, while the neutral line invariably has zero potential. Let's start with Figure 1, where the firewire goes first into the switch and then into the light. If the switch is disconnected at this point, the live wire is cut -- the electric potential at both ends of the lamp is zero. In Figure 2, the live wire enters the light first, and the switch controls the neutral wire. When the switch is off, the neutral line in the line is disconnected -- admittedly, a circuit without a neutral line cannot generate current (or, truly, a sustained current). But the light is still connected to the live wire, in other words, the light is still extremely potential.
The elevated potential at both ends of the lamp creates a potential difference, which in turn creates a weak current. When a tiny current passes through a lamp, it causes a flicker -- a tiny current that really affects the starter of the lamp, whereas an incandescent lamp without the starter would not flicker.
Long-term, not only has an impact on the life of the lamp. When replacing the lights, it will also pose a threat to the safety of the maintenance personnel. Therefore, if this happens, the line should be adjusted in time.
How to determine whether the switch control is firewire? Use an electric pen to measure the switch or lamp junction post. Under normal circumstances, when the switch is disconnected, the switch part of the wire can light the pen, but the lamp part cannot. If the opposite is true, it is proved that the switch controls the neutral line.
In addition, if all the lights in the room are blinking, it is possible that there is an inverted zero-fire connection at the distribution box. At this point, the wiring in the distribution box should be adjusted -- the lighting circuit of the zero live wire switch.
An electric lamp generates a self-induced current
If the wires in the lamp are densely packed, it is possible to generate inductive electricity -- two wires placed parallel and close together will form a capacitor. A high potential (live wire) on one wire and no (neutral wire) on the remaining wire will cause the neutral wire to become live. At this point, the electricity on the neutral line is inductive electricity.
If the current on the neutral line is small, it accumulates on the capacitor inside the light starter until it has sufficient power, and then releases it all at once -- in the appearance of the light flicker. If the current on the neutral line is large, it will continue to generate current on the line, causing the lamp to shimmer.
It is difficult to eliminate self-induced current, and the recommended method is to consume this part of electricity. The method is to purchase a 220V AC relay, and connect the relay coil to the lamp in series. The self-induced current is eliminated by the relay coil.
The current is still diverted after the switch is turned off.
Some switches do not fully disconnect the circuit after being turned off, but still generate a tiny current in the circuit -- I'm talking about the switch with the indicator light. The indicator light of this switch still needs to work after the switch is turned off, so although the switch is turned off, there is still a part of the internal conduction.
This part of the current is extremely tiny, so it does not have much effect on most lamps. But if the LED lamp is extra sensitive to the current, it may cause shimmer or flicker. At this time, there are two solutions, the first is according to the above mentioned series a relay. The second is to remove the indicator light, or replace the switch.