So, does a resistor go before or after a LED?

A resistor can go before or after a LED. The current before and after the LED (and any other point in the circuit) remains the same, so it does not matter whether you place the resistor before or after the LED. The resistor will still limit the current the LED receives so it does not get damaged. 

Why it doesn’t matter if a resistor goes before or after a LED

To better understand why it doesn’t matter whether a resistor goes before or after a LED, we need to learn about current in a circuit.

In electrical and electronic theory, when it comes to closed loop circuits, the current flow out of a battery is equal to the current that flows back into the battery. So what this tells us is that the current at any point along the closed loop is going to be the same. The image below shows a simple closed loop series circuit with a battery source and a LED (let’s assume the battery is supplying the right voltage and current so no resistor is needed). The current before and after the LED (or any point in the circuit) remains the same at 100mA.

Now if we increase the voltage of the battery, we will need to maintain the 100mA of current so the LED does not get damaged. To this we are going  to require a resistor. The main purpose of a resistor is to limit the current in a circuit to protect components like a LED. By adding a resistor to the previous circuit, we are simply dropping the amount of current. 

But, the placement of the resistor does not matter because the current leaving the battery is still going to equal the current re-entering the battery. All the resistor is doing is limiting the amount of current that will flow out of the battery. 

This is why it does not matter whether a resistor goes before or after a LED.

The post Does a resistor go before or after a LED? appeared first on Electronic Guidebook.

Why LEDs need resistors

The main reason LEDs need resistors is to protect the LED from excessive current which can permanently damage the LED. LEDs have current ratings which indicate the optimal current at which the LED operates effectively. Resistors are devices that have the function of limiting current within the current range of the LED making them the perfect component to protect a LED from damage. 

How to connect resistors to an LED?

A resistor is connected to the LED in series. Below is an image of one of the simplest LED circuits which uses a resistor to protect it. 

What size resistor do you require with an LED?

The above circuit shows the configuration of an LED and a resistor in a simple circuit setup. But, you cannot pick any random resistor value and connect it to the LED. Choosing the right resistor resistance value comes down to three variables; Voltage (power supply) , LED current , LED Forward voltage drop.

The voltage source rating is how much voltage is being supplied to the LED. So, for example, the LED could be connected to an AA battery which is usually rated at 1.5 volts. 

As mentioned earlier, resistors are needed to protect LEDs from excessive current. LEDs come with a maximum current rating that should not be exceeded. This is the value of the current that we need for the calculation of the size of resistor needed. The maximum current can be found in the LEDs datasheet.

LED Forward voltage drop is the amount of voltage loss across an LED. LEDs come in a variety of sizes, shapes, and colour, each having their own unique voltage drop. This can also be found in the LEDs datasheet. 

The equation below is used to calculate the size of resistor needed for a particular LED;

R represents the resistance, VS is the voltage of the power supply, V_LED is the LED’s voltage drop, and I_LED is the maximum allowable current for that LED. 

Example of calculating the size of resistor needed for an LED

To better understand how to calculate the resistance needed for an LED, let’s take a quick look at an example. 

Let’s say we want to power a Red LED using a 5 volt power supply. Red LEDs typically have a forward voltage drop of 2V, and a maximum allowable current of 30mA. 

Next, we substitute the values into the equation above;

This gives us a resistance of 100 ohms. So, to properly power the LED and protect it from any excessive current, a 100 ohm resistor is required. 

Resistors for multiple LEDs; Best practices  

We have been discussing the simplest circuit configuration which includes just one LED and one resistor. However, there will be instances where multiple LEDs will need to be connected together. So, how many resistors are needed now?  

There are two scenarios to consider; series configuration and parallel configuration.

Scenario #1: Series configuration

The first scenario is connecting up multiple LEDs in a series configuration. This involves connecting the negative lead of one LED to the positive lead of the next as see below.

When multiple LEDs are connected in series as seen above, the total forward voltage drop is equal to the  sum of the individual voltage drops of the LEDs (as current in a series circuit is shared, but voltage is divided). This means that the voltage source (power supply) needs to be a voltage that is equal to or higher than the sum of the LED voltage drops to ensure the LEDs are powered adequately. 

To calculate the resistor needed in this scenario we still use the same equation as before. However, we first need to add the total forward voltage drops of the LEDs. 

So, if we had three RED LEDs, we know that their voltage drop would be 2V each giving a total voltage drop of 6V (2V  x 3). We also know that the maximum allowable current is 30mA. Now if we had a 10V power supply, plugging these values into the equation (10 – 6/0.03), gives us a resistance of 133 ohms.

Scenario #2: Parallel configuration

The second scenario is connecting up multiple LEDs in a parallel configuration. This involves connecting all positive leads of the LEDs together, and all the negative leads together.

The common practice is to connect one resistor for multiple LEDs. However, even if the LEDs are of the same size and colour, their forward voltage drop can vary slightly. By using one resistor for all LEDs the current will be limited to a value governed by the lowest voltage drop. This will cause LEDs with larger voltage drops to have inadequate power. 

If the voltage drops do not vary drastically across the LEDs used in this setup, then using one resistor for all LEDs in a parallel configuration isn’t an issue. However, to ensure every LED gets an ideal amount of current, individual resistors should be used (as seen below).

Again,  we use the same equation from before to calculate the right resistor needed. In a parallel configuration the voltage is the same across all LEDs. So, to calculate the resistor value for a particular LED in a parallel configuration just substitute the voltage drop of that particular LED (the supply voltage and remain the same). 

Do LEDs require resistors all the time?

There are some instances where a resistor might not be required when connecting a LED to a voltage source. Specifically when the voltage source (used to power the LED) is equal to the forward voltage drop of the LED.

In this scenario, no current limiting resistor is required. For example, if you have a LED with a forward voltage drop of 3 volts, and the power is supplying 3 volts as well, you can connect them without the need of a resistor.

The post Why do LEDs need resistors? appeared first on Electronic Guidebook.

They come in a variety of colours, and lengths (which can be altered to your desire), so you have plenty of options when selecting the right LED light strip to enhance a living space. 

LED strip lights are very versatile when it comes to mounting them to surfaces. 

You can mount them on walls, under tables, around poles, on the floor etc.

But, will LED strip lights stick to wood?  Yes you will be able to stick LED strip lights to wood. It comes with a self-adhesive backing that you can peel off and stick to many surfaces like wood.

However, there are certain things to be aware of that will affect how well the LED strip lights will stick to wood which include; the strength of the self-adhesive, how smooth the wood surface is, and how dirty the wood surface is. 

Things to consider when you stick LED strip lights to wood

As mentioned above, LED strip lights are a versatile piece of equipment and can be mounted a variety of ways on various surfaces using its self-adhesive backing.

However, there are certain things to consider.

Strength of LED strip self-adhesive

Most if not all LED strip lights will come with a self-adhesive backing that will enable you to stick to certain surfaces like wood.

But, not all LED strip lights are created equal which means that the self-adhesive of different branded LED strip lights is going to vary in strength.

Cheaper LED light strips are manufactured using cheaper materials to save on money so that a greater profit margin can be made.

This sacrifice of using cheaper materials will lower the quality of LED strip lights considerably.

So, if a lower quality self-adhesive is used as the backing, it is not going to create a strong bond between the LED strip light and wood. 

But, how will you know what is a good self-adhesive without testing it out?

3M is a company that deals with self-adhesive products as well as tapes.

They are a reputable company known for creating high quality self-adhesive that create strong bonds.

The higher quality LED strip lights will use 3M self-adhesives which means that it will stick better to wood and other surfaces.

You will be able to see if the light strip uses a 3M self-adhesive as it will be written on the back of the LED light strip.

Smoothness of wood LED strip lights will be mounted to

No matter how strong the self-adhesive the LED strip light uses, if the surface of the wood you are sticking it onto is not smooth, it is not going to create a solid bond. 

Consider the diagram below which shows a surface with many imperfections.

When you are applying self-adhesive to a surface, the more surface area you can cover and make contact with, the stronger the bond is going to be. 

If the wood surface you are going to stick the light strip onto is untreated, it is going to have bumps, cracks, and pieces of wood fibre sticking out making it harder for the LED strip light to adhere to. 

So, check the surface of the wood you will be sticking the lights to and ensure it is smooth. 

How clean the wood surface is

If you have applied any self-adhesive to a surface, the instructions always state “make sure to clean the surface of any dirt first before applying the self adhesive to it.”

This is the final check to ensure you create a strong bond between the LED light strip and the wood you will stick it to.

So, you have a strong adhesive, and the wood is smooth, but if the surface of the wood has any dust or dirt, this is again not going to allow the self-adhesive of the light strip to adhere to the surface properly. 

How to ensure the LED strip will stick better to wood

So, now you know that there are a few things to consider before sticking a LED strip light to wood. 

However, just knowing what the problems to avoid are pointless without any solutions to them. 

Let’s take a look at how we can combat these issues.

Strength of  LED strip light self-adhesive – As mentioned above, this comes down to the quality of the light strip which is heavily correlated with how much you pay for it (however on odd occasions you find cheap things that are of high quality). Choose a light strip that uses 3M adhesives as they have a reputation for creating strong bonds. 

Smoothness of wood – If the surface of the wood is not smooth fear not. Get yourself some sandpaper and sand the surfaces that are not smooth. 

Start with a low grit sandpaper (120 – 240) to remove and abrasions, and finish with a higher grit (800 – 1200) to smooth the surface.

Remember to clean the surface after sanding. 

Also, you can paint the wood and finish with polish to further smoothen the surface (but this step is optional). 

Dirt and debris on wood – If you have dirt, dust, or any sort of debris that is present on the surface of the wood, you are going to want to remove it. 

A surface cleaner and a cloth should do the job just fine for removing dirt.

If you do not have a surface cleaner, water should do just fine.

Just remember to let the surface dry before sticking the LED light strip onto it. 

5 other options to mount LED strip lights to wood

If for some reason you cannot follow the steps above, there are other options you have for mounting an LED light strip onto wood.

Option #1 for mounting LED strip lights to wood : Mounting clips

The first option to mounting the light strip onto wood if the self-adhesive is not good enough, is to use mounting clips.

The mounting clip uses a screw to tighten the mounting clip and keep the LED light strip in place. 

Option #2 for mounting LED strip lights to wood : Cable ties

Cable ties might look unassuming at first glance, but do not be fooled.

These little fasteners have many applications but are primarily used in fastening cables and wires. 

Cable ties are a great option when the piece of wood is small enough that you can wrap the cable tie around the wood and LED strip light to keep it in place. 

Option #3 for mounting LED strip lights to wood : Duct tape

If the LED light strip’s self adhesive is not cutting it, consider Duct tape.

Duct tape is known for having a strong adhesion and creating strong bonds.

It is sometimes used to fix problems on aircrafts!

If you opt to use duct tape, just make sure that you do not cover the LEDs when taping the light strip.

Option #4 for mounting LED strip lights to wood : Double sided tape

Double sided tape can be a great option if you already have a set of LED light strips but cannot replace it.

You can invest in a good quality double sided tape that will help you stick the light strip to wood.

Option #5 for mounting LED strip lights to wood : Hot glue

The last option you have is hot glue.

Hot glue is used a lot in arts and crafts for connecting different materials like paper, cardboard, wood, plastic, cloth etc.

It can also be used to create a bond between an LED light strip and wood.

As with the self-adhesive of the light strip, invest in a hot glue gun and glue sticks. 

Cheap glue sticks do not provide a strong bond.

But, just be cautious when using a hot glue gun, as touching the hot glue can be quite painful. 

What if you need remove the LED strip lights later from the wood

Now we have a list of options that you can mount LED strip lights onto wood other than just the standard self-adhesive backing.

Each of these options come with its own pros and cons depending on your needs.

So, what if you need to remove the LED strip lights further down the track?

Using the self-adhesive, hot glue, duct tape and double sided tape is going to leave residue when removing the light strip which might be hard to get off. 

If you require a semi-permanent solution, that can be removed without leaving any residue, go for the mounting clip and cable tie options which won’t leave a mess.

Aesthetics when mounting LED strip lights to wood

If however, aesthetics is one of your top priorities, having mounting clips, and cable ties all over the place is not so pleasing to the eye.

In this instance, using the self-adhesive backing of the light strip or double sided tape would be a better option as these methods are hidden away and are a neater option.

The post Will LED strip lights stick to wood? appeared first on Electronic Guidebook.

LED strip lights are a thin flexible circuit board which consist of surface mount LEDs placed in arrays along the length of the circuit strip.

LED strip lights come in varying lengths from 1M, 2M and 5M spools. 

The beauty of LED light strips is that you can modify them to whatever lengths you desire as they have designated points on the circuit strip where you can cut them.

They have many applications which range from creating ambience in a room, lighting up pathways, decoration, automotive lighting and much more. 

But, can you leave LED strip lights on all night? Yes, you can leave LED strip lights on all night. Your main concern for asking this question might be whether LED strip lights pose any threat to starting a fire. LED strip lights generate far less heat compared to older incandescent light bulbs, therefore it is ok to leave them on all night. 

Or, your other concerns about whether you can leave LED strip lights on all night might be power consumption, and whether it will affect your sleep.

Again, compared to older light bulbs, LEDs consume far less power and are easier on their eyes. 

I shall go into more detail about these three concerns in this article. 

What your main concerns are when leaving LED strip lights on all night

So, you are thinking about leaving your LED strip lights on through the night, and are a little skeptical whether you can do so.

You might have one of the three (or all) concerns below;

• Will LED strip lights start a fire?
• Will LED strip lights cost a lot leaving them on all night?
• Will LED strip lights affect your sleep?

Let’s take a look at each of these concerns separately and in a bit more detail. 

Why it is ok to leave LED strip lights on all night: Fire

Let’s start with the biggest concern of the three; Fire.

There are many potential risks in a home or office. 

One of these risks is a fire. 

While fires are deadly no matter what time they occur, they pose more risk during the night when you are sleeping. 

We all lose our sense of smell when sleeping which makes it harder to be aware of fire when we are sleeping.

This is the main reason for having smoke alarms fitted in your homes. 

So, it is easy to see why anyone would be worried about whether there are fire risks involved when leaving LED strip lights on all night.

If you have ever touched or placed your hand over an older light bulb, you would have felt how hot it can get.

Incandescent light bulbs use a filament to generate light. However, a lot of the energy used to power the light bulb is wasted in the form of heat. 

This amount of heat is one of the threats associated when it comes to fire risks.

LEDs on the other hand are much more efficient at converting energy to light. They used a semiconductor material to generate light.

Due to their efficiency, less heat is generated in the production of light posing a lower risk of starting a fire.

So it is much safer to leave LED strip lights on all night long.

Why it is ok to leave LED strip lights on all night: Power consumption

The next concern you might have is Power consumption.

We all got a plethora of bills to pay.

Whether it be water, electricity, rent, gas, insurance etc.

So, finding ways to reduce the amount of money you need to fork out to pay these bills will help you use that money for something a bit better, like a holiday! 

Electricity is one of those bills where you can make conscious decisions daily which will help you save money.

Things like putting off the lights when no one is in the room, or having shorter hot showers are just some of the many ways to save money. 

But, what if you want to leave a light on all night, to provide a path in case you need to go to the bathroom? 

This is where using LED strip lights instead of older light bulbs is a much better option and will save you money in the long run.

I know that the light bulb was one of the greatest inventions in our history, so forgive me for using it as the bad example in these comparisons. 

LEDs use 85% less electricity than conventional light bulbs! 

This is going to make a significant impact on your electricity bill, and will allow you to leave those LED strip lights on all night. 

Not only are they good for saving electricity, due to their efficiency they have many other benefits;

• Reduce carbon emissions 
• Reduce the amount of waste in landfills (as they have a longer lifespan)
• Stop construction of power plants

Why it is ok to leave LED strip lights on all night: Sleep

The darkness is a scary place! 

That is probably why some of us prefer sleeping with the lights on.

However, studies have shown that sleeping with the lights on can make it harder to fall asleep and stay asleep as your brain will not be able to produce enough sleep inducing melatonin. 

But, fear not, there is a way to work around this problem.

If you cannot go without light when sleeping, opt for red light instead. Research has shown that it can help you fall asleep. 

So, if you are using LED strip lights in your room to help you sleep during the night, opt for the color Red. 

Safety considerations when you leave LED strip lights on all night : Fire 00

While leaving LED strip lights on all night poses a lower risk of starting a fire, there are certain safety considerations to consider to further lower the risk of the possibility of a fire. 

LED strip light  power cable

Ensure that all cables that are connecting the LED strip light cables to the power outlet are not exposed. 

These cables are insulated to protect you and the environment from currents that will be flowing through them.

Damaged cables can cause power surges which can cause your LED strip lights to overheat thereby increasing the risk of fire.

So, double check that all cables are not exposed or damaged.

LED strip light circuitry

Do a quality check of your LED strip light circuitry to make sure all connections are properly soldered and there aren’t any shorts.

A short could cause spark which could lead to a fire.

Cheap LED light strips

This leads to next safety consideration; cheap LED light strips.

With any electrical/electronic equipment, avoid buying low quality items. 

Cheaper electronic equipment like LED strip lights use cheaper components and methods to manufacture to save money.

This ends up with equipment that has poor electrical connections, as well as material that will degrade faster increasing the chance of starting a fire. 

Mounting of LED strip lights

When it comes to mounting LED strip lights, you have many options as they are very flexible.

You can mount them on the wall, under a table, around a pole etc.

But, if you are worried about LED strip lights causing a fire, you will need to think twice before mounting them in certain places, and materials as this will increase the likelihood of a fire. 

Avoid mounting LED strip lights;

• Under or behind curtains, 
• Near flammable items, 
  • Alcohol
  • Nail polish remover
  • Aerosol cans
  • Gasoline, Turpentine, Paint thinner
  • Hand sanitizer
• Under of over rugs
• On carpets
• Near things that catch fire easy like paper, cardboard, plastics etc

Also, water and electronic circuits are not the best of friends.

So, avoid mounting LED strip lights in places like your bathroom or near water sources (even a glass of water which could get tipped onto it).

What to consider when you leave LED strip lights on all night : Power consumption

We now know that LED strip lights are a much more efficient way of lighting a space.

But in saying that if you keep them on all night long you are still adding to your overall bill compared to just running them for a couple of hours.

First you have to ask yourself, do you really need to keep them on all night?

If your answer is not really, as you only want to keep it on for a few hours into the night, you are in luck.

There are devices that allow you to plug in electrical and electronic equipment into (and then plugged into a power outlet) which can be set to turn off after a certain amount of time. 

This will allow you to keep your LED strip lights on for a specific amount of time before turning off helping you save on money. 

What to consider when you leave LED strip lights on all night : Sleep

When it comes to leaving the LED strip lights on for sleep, there are a couple of thing to consider;

• The colour of LED strip light
• The brightness of the LED strip light
• Placement of the LED strip light

Colour of LED strip light – Remember that Red light is the best option (as it promotes sleep as well). Avoid using blue light.

Brightness of LED strip lights – If the LED strip lights have brightness control, make sure to not have it at 100% power. Adjust the brightness to about 25% (or lower) of full power.

Placement of LED strip light – Do not place them right above your eyes, or near your head. Place it in a place that illuminates the room but doesn’t distract you while sleeping.

Can you leave LED strip lights on for a week?

Leaving LED strip lights on for a week should not be a problem as it poses a lower risk of starting a fire and they consume less power. 

However, leaving any electronic equipment on for that long will increase the chances of something going wrong.

So, again first ask yourself do you really need to leave them on for so long. 

If you do, take into account the safety considerations mentioned above.

The post Can you leave LED strip lights on all night? appeared first on Electronic Guidebook.

The light bulb enabled people to light up their homes more efficiently than having to use candles.

Over the past decades however, the discovery of Light Emitting Diodes (LED’s) have proven to be more effective and efficient (about 90% more efficient) than their older incandescent counterparts.

While LED light bulbs do have a longer lifespan, they will eventually stop working and need to be disposed of.

But, how do you dispose of LED light bulbs properly?

The great thing about a LED light bulb is that over 95% of it can be recycled. Since LED light bulbs contain electronic components, it can be disposed of to a dedicated electronic waste (e-waste) recycling facility. 

LED light bulbs can be known for containing nickel and lead.

If not disposed of properly these harmful elements can be detrimental to the environment and people’s health. 

What is E-waste

Electronic waste or better known as E-waste, are products that include electrical or electronic components that are no longer wanted or needed and need to be disposed of.

This can include things like your old tv, mobile phones, stereos, computers etc.

Why is it important to recycle e-waste?

Many, if not all electronic waste contain hazardous materials.

These hazardous materials include, lead, cadmium, and beryllium

If not properly disposed of, they make their way to landfills where they leak these hazardous materials into the ground and waterways which can lead to the sea as well as our drinking water.

Also, most of the trash in landfills gets sent to third world countries where children scavenge through these hazardous materials for metals putting their health at risk. 

LED light bulbs are not as hazardous as many other electronic products, but do contain nickel and lead. 

So, disposing of them the right way will be beneficial to the environment and human health.

How to dispose of e-waste?

We all know that there are recycling facilities that deal with recyclables such as paper, cardboard, plastic, and glass. 

Most of us have a recycling bin at home that we throw those items into. 

But, recycling your old LED light bulb does not mean just throwing it in the recycling bin you have at home.

Doing so will add more work for the people at those recycling facilities as they will have to separate e-waste from the items they can actually recycle (paper, cardboard, glass).

Electronic waste like LED light bulbs, need to be broken down and sepearted because not all parts of it can be recycled.

There are dedicated e-waste recycling facilities that deal primarily with electronic waste like your LED light bulb.

Where can you find an E-waste recycling facility?

I cannot know for certain if there is an e-waste recycling facility in your city, but the best way to find one is to do a quick google search for ‘e-waste recycling near me’ or instead of ‘near me’ you can insert the ‘city’ you live in.

The search results will list all the available recycling facilities near you.

Another alternative is to check with the vendor whom you are buying the LED light bulb from, if they take old LED light bulbs to be recycled.

Most vendors nowadays encourage customers to return old electronic products so they can recycle and reuse components. 

Does it cost to recycle a LED Light Bulb?

Electronic waste that usually incur a fee are bigger products like TV’s.

However, there is no standard rule, and it all depends on the e-waste recycling facility. 

What is an LED light bulb?

An LED light bulb is a more efficient means of illuminating a space compared to its older counterpart, the incandescent light bulb.

It is rapidly becoming the choice in households, businesses and street lighting.

LED light bulbs use Light Emitting Diodes.

When a current is passed through the light emitting diode, photons are released in a process known as illuminessence resulting in the light we see. 

Why is a LED light bulb considered e-waste?

Above, you saw the importance of recycling products that contain electronics as it reduces the harm on the environment and allows us to reuse items.

But, why is an LED light bulb considered electronic waste?

What does an LED light bulb consist of?

The reason that an LED is considered electronic waste is the simple fact that it contains electronic components.

Inside an LED light are the following circuits and electronic components:

• Light Emitting Diodes (LED)
• AC to DC converter
• Capacitors
• Resistors
• Transformer
• Diodes
• MOSFETs

LED light bulb circuitry varies in complexity from one bulb to the next, but these are the common components that can be found inside your standard LED light bulb. 

This is why it is vital to dispose of them by recycling them at dedicated e-waste recyclers. 

Average Lifespan of an LED Light Bulb?

The even better news to the fact that you can recycle your old LED light bulbs when disposing of them, is that they have a long lifespan.

The average LED light bulb lasts up 25,000 hours. 

That’s about 1041 days!

Different types of LED light bulbs

Below are a range of different types of LED light bulbs:

• E27 
• E14
• B22
• B15
• R50
• R63
• PAR38

The process of disposing of any one of them is the same.

Conclusion

So, to reduce the harmful impact that e-waste has on our environment as well as our health, the best way to dispose of that old LED light bulb is to take it to a dedicated e-waste recycler.

They will be able to break down the LED light bulb and recycle materials.How to dispose of LED light bulbs ?

The post How to dispose of LED light bulbs? appeared first on Electronic Guidebook.

Compared to the older conventional light bulb, LED lights are much more efficient and have a longer life span.

They come in a variety of forms such as bulbs, strips, flat panels, or just the individual LED itself. 

You are not limited to the color options as LED’s have a multitude of colours to choose from (colours that cover the entire color spectrum visible to the human eye).

Dimming the lights is a great feature to have in rooms off your home. It can provide a different ambiance and set the mood for different occasions.

So, can you dim LED lights?

Since there are many types of LED lighting options available, it all depends on what kind of LED lighting is being used.

For LED light bulbs, which are connected to light sockets in your home, most LED light bulbs are dimmable. However, not all of them are, and they do not all operate in the same way.

You then have your LED strips, and individual LED’s that run on lower voltages and do not get connected to light sockets. These types of LED lighting can be dimmed by simply lowering their voltage (or connecting to a controller circuit that can dim them).

Since you cannot lower the voltage of a LED light bulb, you need special dimmer switches to carry out this task.

In this article I will dive deeper and cover more information regarding what kinds of LED light bulbs you can dim and what is involved in dimming them.

What is dimming?

Dimming a light is essentially the ability to change its brightness.

A normal light in a household which does not have a dimmer circuit, would be operating at its maximum brightness when turned on.

Dimming allows the brightness to be varied from 100% all the way down to 0% (which looks like it is turned off but it is not). 

Sometimes having the lights at full brightness can be quite annoying as they can have an effect on your eyes overtime. Having the ability to dim a light source can be beneficial. 

By dimming the lights you lower the amount of power consumed by the light therefore cutting costs to your power bill.

What is a dimmer?

Being able to dim your lights does not just happen by magic.

It involves something known as a dimmer circuit. Their purpose is to allow you to be able to alter the brightness of your lights. 

The way the dimmer circuit does this is by changing the voltage waveform applied to the light. 

The dimmer circuit rapidly shuts on and off, reducing the total energy that the light bulb receives. The lower the energy the lower the brightness and the higher the energy the brighter the light bulb.

Dimmer circuits are generally used for light outputs that include incandescent bulbs, halogen bulbs, compact fluorescent lights and Light emitting Diodes (LED’s). 

Older dimmers were built using resistors. Resistors are not the most efficient way of dimming circuits due to the fact as the resistors heat up, a lot of energy is lost. 

Therefore, modern day dimmers are built from semiconductors to increase the overall efficiency.

Types of Dimmers

Through the years the dimmer has seen many upgrades from its humble beginnings. 

It all started with the Rheostat Dimmer. This type of dimmer primarily used a rheostat (of course!). 

A rheostat is an electronic component used to control the flow of current by varying its resistance.

This type of dimmer was inefficient because a lot of power was lost through heat. They were large and needed cooling air to reduce the heat.

Also, due to the fact they had mechanical parts, they were slow, again adding to its inefficiency. 

A common early use of a Rheostat dimmer was the Saltwater Dimmer which used a liquid as a form of varying its resistance. 

Next came the Auto-transformer dimmer. Also sometimes referred to as a VARIAC.

Though the Auto-transformer was as large as a Rheostat dimmer and were quite similar in resemblance, they were more efficient.

The output voltage which is used to vary the brightness of a light, was independent of the load applied in an Auto-transformer. This led to easier design of the lighting.

Nowadays, Auto-transformers are no longer used for dimming applications.

Lastly we have the Solid-State Dimmer. The solid state dimmer uses semiconductors to perform dimming. 

They were developed in large part to reduce the problem of inefficiency that were present in the Rheostat and Auto-transformer dimmers. 

The main benefit that reduces the dissipation of power is that solid state dimmers switch the voltage rather than absorb it.

It also has the added benefits of being controlled remotely and small enough to be embedded inside a household light switch.

Application and Benefits

Having the ability to dim the lights can have many advantages.

Light levels in a room can affect your mood without you even knowing. It affects things like the way we work, and the way we feel. 

The softer the light level the more comforting and relaxing. While brighter light levels are more stimulating and good for keeping you awake.

Softer lighting is great for setting the mood for things like watching a movie, or having a romantic dinner with a loved one. Or, maybe you are someone who likes sleeping with the lights on. A softer light will solve this problem and eliminate having to try to sleep under light that is at full intensity.

Brighter lighting is great for when you need to do work or need a good amount of light for reading.

Having different rooms that have different light levels is not ideal, but, the light dimmer is the perfect solution.

You can have the benefits of softer and brighter lighting all in one room.

The Light Bulb

One of the main pivotal points in history was the invention of the light bulb. We can thank Thomas Edison for that. 

Before the light bulb people would use candles to light up their homes so they could carry out tasks like cooking, bathing, reading etc.

While candles were handy, they were not the most effective, as they only lit small spaces at a time.

Light bulbs allowed one to light up more areas in their house at the flick of a switch.

The dimmer circuits that we have covered were used in conjunction with these older incandescent light bulbs. 

Over the years however, light bulbs have evolved from the older incandescent bulbs to newer more efficient Light Emitting Diodes. 

Light Emitting Diode

If the incandescent bulb was a crucial invention in lighting, the Light Emitting Diode (LED) was a crucial innovation.

Compared to Incandescent, Halogen and Compact Fluorescent bulbs, LED’s require far less energy to operate.

They use 75% less energy to run. This means that in the longer run you save more money on your power bills. 

They also have a longer life span, again saving you money by having to buy less of them.

A LED is a tiny semiconductor known as a Diode. A diode is a device that restricts the flow of current in one direction.

This flow of electrons creates photons (which is the light we see).

LED Light Bulbs

So, you can see the many benefits of using a LED light bulb.

But, can you dim all LED light bulbs?

It all comes down to two factors; whether the LED light bulb is designed to be dimmed and whether your dimmer is LED compatible.

Not all LED light bulbs are designed to be dimmed. The ones that can be dimmed are designed with a special circuit embedded inside them that allows their brightness to be varied in response to a varying current.

So, your ability to dim a LED light bulb all depends on this factor. When buying a LED light bulb, you need to verify that it is ‘dimmable’. 

Most of them will state this in the title, or you can check the product description.

So you have a dimmable LED light bulb. But, what about your dimmer circuit, will it be able to dim them?

There are two types of dimmer circuits; Leading Edge and Trailing Edge.

Leading Edge dimmers are designed to work with older incandescent bulbs. These sort of dimmer circuits would be found in older households. 

These types of dimmers were designed to work with traditional bulbs due to the fact that they were higher wattage. Since LED light bulbs are low wattage leading edge dimmers will not be able to dim your LED light bulb.

Trailing Edge dimmers are designed to work in the lower wattage range and therefore can dim LED light bulbs (the dimmable ones of course!). 

How do you tell if you have a Leading or Trailing Edge dimmer? 

Since, dimmer circuits deal with high voltages, it is not advisable for you to open your light switches and check.

You will have to contact the manufacturer to find out what kind of dimmer circuit you have installed.

You could get an electrician to come and have a look as well. Or, you could just install your LED light bulb and check if the brightness of the light is varied. The worst that could happen is that you blow the bulb.

If your home was built within the last 5 years, and you have a dimmer, it is likely that it is a trailing edge dimmer and compatible with LED light bulbs.

If you have identified that you have a Leading edge dimmer do not worry, you can make the switch (pardon the pun) to a Trailing Edge dimmer.

The cost can range from $60 to $150 and depending on the brand of the dimmer and the cost of labor.

As I mentioned before, for your own safety, it is advisable to hire an electrician to remove and install the new dimmer.

Conclusion

So, in order for you to be able to dim an LED light bulb, it needs to specifically designed to be dimmed.

You can find this information in the product description of the LED light bulb in question.

Also, your dimmer circuit needs to work in conjunction with LED light bulbs.

These dimmers are most commonly the Trailing Edge Dimmers.

Always consult an Electrician if you need to check what type of dimmer you have, or, if you want to replace an existing dimmer to the newer ones.

The post Can you dim LED lights? appeared first on Electronic Guidebook.