What is the reason why the light tube flashes after turning off the light

It's strange to turn off the light and lie in bed, preparing for a beautiful sleep, only to find that the light on the ceiling is still flashing. Now let me introduce the reason why the light tube flashes after turning off the light. I hope it can help you.

1. It is always on after turning off the light

If the light is as bright as when the light is turned on, there is no doubt that the switch must be broken. The internal structure of the electric light switch is very simple, and only one contact is responsible for on and off.

In case of unstable voltage, short circuit or poor switching quality in the circuit, the contact may be burned. The burned switch has two manifestations: one is that it can't be pressed, and the other is that it can be pressed but can't be controlled. After turning off the light, the electric light shines normally, which belongs to the latter situation.

Check whether there is overload or short circuit in the circuit and replace it. Voltage instability may occur in some areas or new buildings. If the voltage is too high, the switch may be burned. At this time, you can choose to buy high-quality switches. There is no good way.

2. Light up slightly after turning off the light

It refers to the weak and continuous light emitted by the electric lamp after the electric lamp switch is disconnected.

If the tungsten wire of incandescent lamp is lit for a long time, or the tungsten wire becomes thinner after aging, it may show weak light after turning off the lamp. However, the low light level of incandescent lamps often doesn't last long and will soon go out.

If this happens, don't worry. It can be solved after replacing the bulb.

The fluorescent tube is filled with argon. The luminous principle is to generate heat through the ionization of argon. The heat makes mercury produce steam. The mercury vapor is ionized and emits ultraviolet light. When the ultraviolet light passes through the fluorescent material on the tube, it emits light visible to the naked eye.

When the fluorescent lamp works for a long time or the working environment temperature is high, the internal temperature of the lamp tube will be high after turning off the lamp. In this way, the lamp tube will be slightly bright after turning off the lamp.

The luminous rate of LED is high, so it is sensitive to current. LED bulbs or tubes with low power often have no starter, so it is easy to turn off the light and turn it on slightly.

However, LED lamps with higher power, such as ceiling lamps, will be equipped with a constant current starter, so this will not happen.

No matter what the light is, the problem of slight light after turning off the light will not be too big. If it can be tolerated, it can not even be solved. Moreover, after turning off the light, it is slightly bright and will not consume electricity.

5. Flash after turning off the light

It can almost be concluded that the switch controls the zero line.

The gas inside the fluorescent tube can be regarded as a capacitor. If the live wire directly enters the electric lamp, there is still voltage at both ends of the electric lamp after the lamp is turned off. At this time, the capacitor will be continuously charged and discharged, so that there is periodic weak light inside the fluorescent lamp.

① switch control live wire

If the live wire directly passes through the electric lamp, there will be a continuous voltage at both ends of the lamp bead. The sensitivity of LED beads is high and flickering will occur.

No matter what kind of lamp, even if it is an incandescent lamp that does not flash, if the switch controls the zero line, it should be corrected in time. The switch controls the zero line, which is extremely harmful and will not be repeated here.

② line leakage

If the phase line around the electric lamp leaks electricity, the LED lamp will reflect it.

③ induced current

If the wires around the lamp are dense, it is possible to generate induced current inside the LED lamp. At this time, a capacitor or relay coil can be connected in series on the LED lamp.

Note: when replacing or repairing the electric lamp, be sure to ensure that the electric lamp is turned off. If there is a problem with the circuit or the state of the light switch cannot be determined, the switch in the distribution box should be disconnected directly.

Incandescent lamp / energy saving lamp / LED bulb

The bulb of this lamp is rotationally installed in the lamp mouth. When removing, it can be rotated counterclockwise. When installing, rotate clockwise.

It should be noted that when removing the bulb, hold the lower half of the bulb, that is, the part closest to the lamp port, so as to avoid damage to the bulb during removal. During disassembly, do not touch the metal part at the bottom of the bulb to avoid electric shock.

Fluorescent tube / LED tube

During disassembly, hold one end of the lamp tube with your hand and push it to the other end to remove this end. Then pull it to this end to remove the other end. When installing, first install one end, then hold the non installed end of the lamp tube with your hand and push it to the other end.

If it is an LED lamp, you also need to pay attention to the identification of the positive and negative poles on the lamp.

Energy saving ceiling lamp tube

The energy-saving lamp tube has various shapes such as round and M-type, and its installation method is the same. After removing the lampshade, you can see the image above. The red circle part is the connecting part between the lamp tube and the chassis. When removing, hold the hoop part with your hand and pull it down with force to successfully remove it. When installing, hold the hoop part and insert it with force.

U-shaped lamp tube

U-shaped lamp tube is mainly used for table lamp and Yuba. It is divided into separate lamp tube and integrated lamp tube (multiple separate U-shaped lamp tubes are connected together), and their installation methods are plug-in type, which can be plugged in and out directly.

Ceiling spotlight

As shown in the figure above, there are a pair of safety clips on the back of this kind of lamp. During disassembly, hold both sides of the lamp shade by hand and pull down, and the spring will expand. Before the lamp is completely removed, press and hold the springs on both sides by hand to avoid injury caused by the fall of the spring after the lamp is completely removed.

After removal, there will be a white square box, which is the drive. The drive does not need to be moved. The driver and the lamp are connected by a black clip, which can be pulled out.

During installation, push the spring upward, insert it into the ceiling opening, release the spring and let the spring fall back naturally.

Led ceiling lamp

The LED lamp wick and rectifier are integrated. When replacing, remove the original rectifier and directly replace it with a new one. The wick is fixed on the chassis by screws or magnets.

The LED is driven by the same shape, but the problem can be solved when the LED is replaced. Generally, led beads will not break. In extreme cases, if they are damaged, they can be replaced with patches of the same shape. See the disassembly drawing below.

II: there are many choices for the specifications and shapes of fluorescent products. Today, we will focus on the selection of several main models

1: two pin fluorescent tube (conventional wattage and size) (select according to the light source specification of your lamp)

2: four pin H-tube light source (flat four / square four) (conventional wattage and size) (select according to the light source specification of your lamp)

3: square four pin fluorescent tube (conventional wattage and size) (selected according to the light source specification of your lamp)

4: flat four pin fluorescent tube (conventional wattage and size) (selected according to the light source specification of your lamp)

III: the third kind is generally used for G9 lamp beads of IKEA lamps or unconventional lamps

IV: if the lamp still cannot be lit after changing the bulb, the ballast should be considered.

The ballasts of various lamps shall be used according to the wattage of their light source.