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Why Do LED Bulbs Glow When Switched Off?

Why Do LED Bulbs Glow When Switched Off?

Sometimes your LED bulb glows even after switching off. It may sound funny while, on the other hand, annoying, especially if you want the lights off. So, why do LED lights continue to glow after switching off?

The LED lights contain some diode, especially in the low-quality bulbs. The diode picks up even the slightest electric supply, making it light up the bulb. This feature is unique in LED bulbs. Let’s find out why the LED bulb glows and fix the issue. 

Why is My LED Light Bulb Glowing When Off?

To fix the issue of LED ghosting, you should understand the cause to solve it and bring efficiency. Also, you shouldn’t intervene without knowing the root cause, as it can lead to more serious consequences. The reasons your LED bulb glow include:

Residual Electricity 

This phenomenon occurs when a low current is still present in the LEDs diode. The LED bulbs pick it up and convert it to light energy. LED is the only bulb that picks up residual electricity since it’s highly efficient. 

Faulty Circuit

When a circuit has an issue, the light switch will let out electricity even when you turn off the switch. So, the glowing will occur in two ways; due to wrong wiring or high- resistance. If the neutral wire isn’t earthedor has high resistance, it can leak a small current to the bulb. This current can power an LED bulb and glow when turned off.

Wrong wiring is the most common issue, especially to the switch. When connecting a hot wire to the switch, it can mistakenly attach the coil wire. The incorrect wiring releases low voltage, making the LED bulb glow dim when the switch is off. 

Fancy Switches 

Some switches have special features like indicator light, timer, and motion sensors. Unfortunately, these features require some power to be on stand-by. LED can draw this small current and light faintly even with the switch off.

Poor Quality Bulbs 

Bulb’s quality varies a lot depending on the market. Sometimes you find the low-quality LED bulbs glowing, buzzing, or flickering even with the switch off. 

Glowing Luminescent Layer 

White light is produced by combining blue LED with an extra phosphor or luminescent layer. This layer can store a certain amount of light depending on the material used. However, the stored light can only last for a while, probably a few minutes. So, if your LED glows for some minutes after turning off and the light disappears, most likely it has this layer. 

Electronic Dimmer 

We have two types of dimmers; conventional and electronic dimmers controlled by a rotary knob, pushbuttons, or touch. Some electronic dimmers, especially from the era of halogens lamps, fail to meet LED bulbs specifications. These dimmers require a minimum load to function, which fails to align with LED economical design.

If the load falls below the minimum, the dimmer fails to turn off the output voltage completely. So even with the switch off, the LED continues to glow. 

Parallel Cable Routing

There are usually two-way connections in a building with long corridors and staircases. The connection requires several switches to control the lights. This system becomes a drawback due to the parallel cable routing over long distances. 

The high-voltage conductor induces a voltage in the conductor separated from the switch. Some low voltage thus gets into LED bulb even with the switch off and lights the bulb. 

How Do I Stop My LED Bulbs from Glowing?

There are several ways you can stop LED lights from glowing when off. Some ways are easy to apply, while others require an electrical technician. The following are the solutions to apply:

Change the Bulb

Sometimes the issue may be the bulb, especially if it’s poor quality. You need to purchase another bulb and ensure it’s from a trusted brand with the best quality.

Earth the Neutral Wire 

If the problem isn’t the bulb, then it’s electrical installation. One of the electrical issues is having a neutral wire earthed incorrectly. Therefore, it’s best to call an electrician to check your wiring. The technician should do appropriate earthing to correct the problem.

Install a Zener Diode

Sometimes the afterglow occurs due to electromagnetic induction caused by residual voltage. To control this, consider having a Zener diode. This element regulates the circuit’s voltage and blocks excess current when the system is off. 

Connect Extra Capacitor 

Use extra capacitors in the long hallways with two-way connections. Sometimes the voltage-carrying conductor induces some charge to the other conductor. This voltage triggers the afterglow in the LED. So, the extra capacitors will seep the excess charge and eliminate the afterglow. 

Set Up a Neon Indicator

Install a neon indicator between the neutral and the lone bulb at the end of the wire. The indicator will take up the excess charge and glow instead of the bulb. Check the voltage that the indicator can manage and install an appropriate one. 

Use LED Dimmers 

When replacing a bulb, always ensure you match it with the appropriate dimmer. Using the correct dimmers ensures no LED lights even after the power is off. Also, compatible dimmers ensure you have a dim light bulb with a switch on in your rooms. 

Is it Normal for LED Lights to Glow When Off?

It’s normal for LED to glow for up to a minute after switching off the power. This glow that lasts for a few minutes occurs due to the luminescent layer that the bulb has. Thus, this glow is normal, and no need to worry. 

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However, if the glow persists for a while, this might be a sign of trouble. If you try to change the bulb and nothing works, you may be having electrical wiring issues. You should consult an electrician to examine your system and correct it accordingly.

Conclusion 

Everyone around wants to save energy by switching to LED bulbs. The LEDs have low energy consumption and are durable. So, it’s worth investing in LED bulbs. However, the glowing issue shouldn’t hinder you as this article has several solutions to fix it. Some are easy to apply, like replacing the bulb, while others need an electrician’s help. 

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