Why LED lights blink: troubleshooting + how to fix

Today people are massively switching to using energy-saving lighting devices.This is done with the hope of obtaining a number of important advantages, including efficiency and durability.

But it often happens that instead of the expected result, users immediately encounter signs of a malfunction. Therefore, the question of why LED lamps blink arises quite often for consumers.

In this material, we will look at all the most common causes of blinking LED lamps, and also talk about ways to find a fault in lighting equipment.

Why do cheap lamps flicker?

There are probably no people who have not heard that you should not buy cheap products from little-known manufacturers, as this is fraught with negative consequences of varying complexity.

This also happens in the case of LED lamps, which often begin to blink even immediately after purchase, which does not make the owners happy at all.

Flashing LED lights are quite common. However, in most cases they remain operational and, if the cause is eliminated, they will be able to function for years

But this mode of operation in most cases does not indicate the presence of a breakdown. That is, the lighting device is usually in good working order, but it is exposed to some unfavorable factors that interfere with its normal functioning.

And if they are eliminated, the flickering will stop, and there will be no relapses. But it is more practical to prevent such phenomena, and all that is needed for this is to purchase high-quality products from well-known manufacturers.

At the purchase stage, they will cost more, but high performance characteristics will ensure long-term operation. Moreover, without losing the best properties, and this costs a lot. Since cheap lighting devices allow you to save only on price.

And then a person is faced with their predisposition to various malfunctions and other negative consequences, including negative effects on health.

Modern LED bulbs are always complex technological devices consisting of many components. Among them is a driver whose task is to stabilize the electric current.

And this is an important task, since high-quality and long-term work depends precisely on its characteristics, and not on voltage, as many believe.

Additionally, the driver is able to cope with various side factors that lead to flickering in the off/on position of the switch.

Every user should be aware that only cheap LED lamps made by various little-known manufacturers are prone to flickering. So you just shouldn't buy them.

But it is a mandatory part of the design of only high-quality and, therefore, expensive lamps. And in their affordable counterparts of Chinese and even domestic origin, to save money, this key element is always replaced with a cheaper power supply.

It is based on such design elements as a diode bridge equipped with a capacitive filter and a quenching capacitor.Which are able to provide high-quality lighting only when the characteristics of the electric current are ideal.

In this case, the work cycle looks like this:

1. Initially, the alternating current passes through the diode bridge, where it is converted into the constant current needed for LED lamps, but with high ripple.
2. To give the electric current stable characteristics, it is fed into a capacitive filter. And from there to a damping capacitor, which finally smoothes out the ripple.
3. Current with the required characteristics goes to the lighting devices, allowing them to perform their duties properly.

But with non-ideal electric current parameters, the power supply with its cheap components is not able to cope with ripple and its rectification, which ultimately causes blinking.

Either one lamp or a whole separate group can blink. However, the reasons for this phenomenon are the same. And they should be eliminated promptly. Otherwise, the life of the lighting fixtures will be exhausted in a short time.

In addition, signs of such a malfunction can appear both in off and on states.

And the features of each type of emergency work should be known, as this will help eliminate the defect. Moreover, quickly and often without any serious costs.

Blinking when the switch is off

This type of malfunction occurs due to the fact that electric current, even when the control is not in working position, enters the smoothing capacitor.

There it accumulates and, when the entire available volume is filled, it enters the launch circuit, which tries to bring the LED lamp into the working position.

But the tiny reserve of electricity is only enough for a short-term flash. Then the procedure begins again and can continue until the cause is eliminated or the lighting device breaks down.

Reasons for abnormal work

The blinking frequency varies and depends on the amount of electric current passing through the power supply of a cheap lamp.

But you need to understand that this is not the cause, but only a consequence of the improper functioning of other elements of the circuit. And you should know them in order to cope with the task, and without unnecessary costs and loss of time.

The consequence of a malfunction in the form of blinking can occur in any position of the switch. This should be understood in order to diagnose the cause in time

Despite signs of malfunction, the product, in most cases, remains operational. The power supply simply cannot prevent instability by smoothing out the ripple.

One of the LED lamps blinks due to the following stimuli:

• switch backlight;
• induced voltage;
• presence of leakage currents.

Since knowing the signs of the causes of a malfunction will help to identify them and promptly eliminate them, you should deal with each of them separately. Moreover, this will be possible for a user far from this sphere.

Flashing due to switch illumination

For convenience, many manufacturers equip their switches with backlights. And in most cases, they provide a benefit by increasing the comfort of owners, as they are easier to find in the dark.

But when using such a control in conjunction with inexpensive lamps, the current supplied to the backlight LED can cause blinking. This happens because the specified structural element is connected in parallel to the switch itself.

This feature leads to the fact that in the on position all the electric current goes to power the LED lamps used, and in the off position it provides illumination.

It is important to remember that blinking can be visible and invisible. Moreover, if in the first case there is often a risk of premature wear of the lamp elements, then in the second case people’s health will suffer significantly. Namely, this threatens nervous system disorders and partial loss of performance

In this case, a small amount of electricity can get further to the capacitive filter and quenching capacitor, and then, having reached the desired performance characteristics, it gets to the lamps, causing blinking.

Moreover, this reason is the most common, so the user should always remember it. And when restoring the functionality of lighting in the room, attention to switch illumination It is always worth paying attention, and first of all.

Blinking due to induced voltage

In the post-Soviet space they often like to skimp on quality. So the induced voltage is a consequence of this. Since most often it occurs when one stranded wire is used to power several devices, and not several, as expected.

Although it sometimes happens that when laying independent electrical wiring lines in one groove, interference may also occur due to the induced voltage that appears.

But this only happens in disconnected areas. And usually the influence is exerted by the wiring that powers electrical appliances operating under heavy load.

Even the lowest-power incandescent lamp, which must be installed instead of one of the LED lamps, can quickly eliminate flickering.This is not aesthetically pleasing, but will give time to take other measures

And although such interference is insignificant, it is enough to influence LED lamps. Which, as a result of active influence, begin to blink frequently, which leads to their rapid failure.

And the worst thing is that the lighting fixture purchased as a replacement will face the same negative factors.

When do leakage currents cause a problem?

This reason is the most serious of all possible. Since the abnormal operation of any LED lamps can be caused by quite fire-hazardous reasons.

These include:

• incorrect or poor-quality electrical installation;
• damaged or deteriorating insulation;
• bad contact.

Often, when performing work, the human factor plays a role and specialists violate all sorts of basic rules.

As a result, after the circuit is broken, that is, when the switch is set to the non-working position, current still flows to electrical appliances. This happens if zero is confused with phase.

Damage to the insulation can occur due to careless handling of the wire during installation or operation. In addition, it often loses its performance characteristics after prolonged use, that is, when its resource is exhausted.

The backlit switch is the most common cause of abnormal operation of any LED lamps. Since the current from these elements enters the smoothing capacitor, which, performing its functions, stabilizes it and, when the required volume is reached, supplies it to the LEDs

Another reason for the appearance of leakage currents is poor contact between the wires and other circuit elements.This happens even during normal oxidation, which can happen within a few years after the start of their use, and even faster in difficult conditions.

Ways to eliminate the causes of blinking

If the blinking occurs due to the presence of a backlight lamp, then the simplest way to restore normal operation is to break its circuit. That is, you need to dismantle the switch and simply cut the necessary wires.

This will not affect the characteristics of the electrical appliance, but the backlight will not function in the future. In addition, a simple method is to replace the switch - this can be done quickly.

You should also know that there are two types of lighting: neon and LED. And when using the first, flickering is much less common - this is information for those who do not want to complicate the search for a switch in the dark.

If you are using a switch with a backlight on each key and not all the lamps are flashing, but only part of it, then this means that current is flowing through only one control and it should be replaced

If a group of LED lighting sources is used, then instead of one of them you can install the lowest-power incandescent lamp. It will act as a resistor, converting current into heat and dissipating it into the air.

In this way, flickering can be avoided, but the aesthetic properties of the chandelier will deteriorate significantly. Since in most cases it will not be possible to disguise an incandescent lamp.

Another proven option for eliminating the causes of abnormal operation is to add a low-power resistance of 50 kOhm to the circuit, with a power of 2 W.

But it should be understood that such an element increases the fire hazard.Therefore, the work must be done efficiently and the isolation of contacts must be handled equally responsibly.

The consequences of exposure to induced voltage are most often eliminated using the above methods. But it happens that signs of malfunction do not disappear.

For example, sometimes you can observe blinking even after replacing the switch with an analogue without backlight. In this case, the only effective option would be to replace the cable, and if there are several of them, then it will be necessary to place them at some distance from each other.

Any damage to the insulation can not only cause the lamps to flicker, but also pose a health hazard to users

Leakage currents can only be eliminated by checking the correct electrical installation and eliminating deficiencies, that is, replacing circuit elements in poor condition.

In the worst case, you will have to replace the wiring in the entire apartment. This is especially true when a room with a flashing light uses a long-outdated and ineffective TN-C grounding system, which does not exclude the possibility of electric shock to a person.

Flashing when the switch is on

In this case, there may be only two reasons, so it is easier for the user to find and eliminate them. But you should remember that this needs to be done quickly, since the durability of LED lamps depends on this.

The reasons for blinking may be:

• low voltage;
• poor quality power supply.

All LED lamps are sensitive to low voltage, but high-quality specimens with a driver instead of a power supply are able to operate stably within 180 V. While the economy options completely stop working - they go out, they simply don’t turn on - already at 200 V.

And, if the voltage is slightly higher, but does not reach 220 V, then the user will observe flickering at different frequencies. Moreover, it will stop when the network parameters stabilize to normal.

Poor contact between wires and other circuit elements is considered another common cause of lamp malfunction. In addition, they increase the fire hazard and pose a health risk.

The malfunction may also occur when you try to dim an LED lamp that is not intended for this purpose. In this case, its performance at the maximum position of the brightness control will be normal, but when you try to decrease it, flickering will begin.

Instructions for connecting a dimmer can be found in this material.

If the voltage in the network turns out to be normal, then you should pay attention to the power supply of the product being used. The reason, as described above, may be that its components simply cannot smooth out the current ripple that leads to blinking.

Any stranded wire used to supply power to multiple appliances is often the cause of flickering. Therefore, it is considered a clear example of dubious savings

To prevent abnormal operation in any of these cases, you can set stabilizer, which will provide the current with the necessary parameters, and at the same time prevent premature breakdowns of electrical appliances used by the owner.

If the voltage is normal and the reason is poor-quality components of the power supply, then the user will be able to upgrade it. To do this, it is necessary to replace the installed smoothing capacitor with a more powerful one, and an advanced user will be able to independently assemble a reliable driver.

Moreover, this characteristic is limited not by parameters, but by the size of the free space in the power supply and lamp base. This guarantees smoothing of current ripple and ensures stability of its parameters.

How to find the reason correctly?

Each user must remember that prompt action to eliminate blinking is very important. Since any LED lamp has a turn-on life, which can be used up in just a few days.

In addition, if the wiring or its insulation is damaged, there may be a danger to human health.

The presence of several cables in one groove can lead to induced voltage. The impact of wiring designed to power a powerful electrical appliance is especially strong.

The search itself must begin by checking the correct connection of the phase wire. It should always be connected to one of the switch contacts.

If it turns out that the current is approaching the backlight lamp, then this will be the cause of the blinking. The check can be done using an indicator screwdriver, which anyone can do.

When this stage has been completed and the malfunction has not been eliminated, you should replace the switch with a similar product without backlighting, install a low-power resistor, or use an incandescent lamp. If the flickering has stopped, then we can assume that the person has completed the task.

The most effective way to prevent flickering is to purchase quality lamps. If you don’t want to spend money, then you need to check for hidden flicker in the cheap analogues you buy. What can be done by quickly moving an ordinary pencil, if the silhouette does not begin to double, then the lamp is not prone to blinking

But, when the problem manifests itself again, you should inspect the wiring in order to identify damaged insulation, oxidized contacts, power cables laid nearby and other problems.

Which will need to be eliminated even if such operations turn out to be labor-intensive and expensive. Because only this can guarantee that there is no danger to human health.

If flickering occurs when the switch is in the on position, then the voltage and its stability are initially checked.

When the parameters are normal, you should replace the LED lamp with a high-quality analogue from a well-known manufacturer. Which are high-tech products from OSRAM, Philips and a number of others.

Conclusions and useful video on the topic

How to return the lamp to functionality by installing the resistance is demonstrated in the video:

The following video provides an overview of several more ways to eliminate the blinking of various LED lamps:

Flashing LED lamps is a very common phenomenon and there is no need to be afraid of it, since in most cases it is easy to fix. In most cases, it is enough to change the switch.

But the very manifestation of such a deficiency indicates that cheap and low-quality products are used that do not inspire confidence in the manufacturers. And the imaginary savings come at a cost of additional expenses and wasted time on trifles.

If you have the necessary experience or knowledge, please share it with our readers. Please leave your comments and ask questions in the block below.