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Can You Put LED Lights on a Dimmer?

Can You Put LED Lights on a Dimmer?
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A great way to immediately start saving energy and money on your electric bill is to start out by changing your old bulbs to LED’s. Not only will a new LED save you on your electric bill but they have a much longer lifetime, smaller in size and they even have faster turning on and off times.

One thing to be careful of though is that not all LED’s are compatible with existing dimmers and vice versa.

Types of LED dimmers

To better understand the two types of dimmers you must basically think of a sinusoidal curve or a sine wave which is basically what is created with AC power. AC power is what feeds pretty much all grids world wide.

Leading Edge Dimmer

You can think of the leading edge dimmer as taking the second half of the sine wave. For the less mathematical type of person you can even think of this like a wave of water from the ocean, lake or even pool. If you paused a wave and vertically cut it in half at its peek you wind up with two halves.

The leading edge dimmer can be thought of as the second half of the wave in which the light is on at the peak of the wave (the starting point). Similar the downside of the second half of the wave the light is shutting off.

This is how the power supply manages the current through the diodes which is allowing multiple diodes to keep the light lit at a less than full brightness (See Pulse Duration Modulation Below for more details).

Trailing Edge Dimmer

The trailing edge dimmer works the exact same way but inversely. You can think of this as the first half of a wave. When it starts out down low the light is turning on and as it reaches the peak of the wave it is turning back off.

LED’s can in fact work with both the leading edge dimmers and the trailing edge dimmers but the trailing edge has quite a few advantages. This is why most LED’s are designed for the trailing edge dimmers and not the leading edge.

LED Dimmer Capable Bulbs

Now that we know that LED’s can be designed for two types of dimmers, it kind of goes without saying that we need to confirm we get the correct type. There shouldn’t be a need to dive that far into those details though.

In order to figure out if your LED is compatible with your dimmer simply look at the LED description to confirm it truly is a dim-able LED.

Another option would to simply buy just one LED bulb and give it a try. Since most of them these days are compatible the probability of having to return it for a different one is slim.

Another thing to look for is to confirm it is an energy start bulb. Not only is this a certified bulb but 99% of them are certified for use with a dimmer. This will not only help confirm you are getting a LED that will work with a dimmer but energy star bulbs are rated to last more than 13 years.

What Does LED Stand For?

LED stands for light emitting diode. The diode is a semiconductor that basically emits light as current passes through it. After years of research and development different colors can also be produced including colors the human eye can’t even see similar to infrared.

This is also cool because it will allow you to select a bright white light for things that really need to be lit up, like a kitchen or a warm light which is better for late night reading.

Why Don’t All LED’s Dim?

While today most LED’s you buy will be dim-able there are still quite a few that wont. This has to due with some older technology that is still out there which doesn’t have the pulse duration modulation or pulse width modulation functionality equipped.

What is Pulse Duration Modulation or Pulse Width Modulation? (and how does it work?)

Pulse Duration Modulation or Pulse Width Modulation has a power supply that allows the current to be cycled through more than one diode / semi-conductor. When the dim-able LED is on full blast all semi-conductors are getting equal power producing the designed amount of LED light.

When you lower the dimmer switch the power supply will start to cycle these semi-conductors in which not all of them are on at the same time. You can’t see or tell that it is going on but 75% of the diodes will be emitting light while the other 25% are off and they cycle through so not all diodes are staying on or off.

When you lower the dimmer even more it will drop down more to a 60% of the diodes are on and 40% are off. As you keep lowering the dimmer it will continue to progress downward in which some will be 50% on, 50% off or 25% on and 75% off, so on and so forth.

It is a super cool technology that we all use every single day. This is whether we know we have it installed in our house, apartment, condo or if we are out at a restaurant, grocery store or even movie theater.

The best part about it is that LED’s are more efficient and have a longer life then regular bulbs which allows us to save money on energy along with saving money on frequency of replacing the actual bulb.

How Much Can a LED Save Me?

In simply running some numbers lets see how much we can save by swapping out one typical existing bulb for a typical LED bulb.

If we pull out a 100 watt bulb and replaced it with a 9 watt LED bulb lets see what could be saved. Assuming the electrical cost is .154 $/kWh we can crunch some numbers and assuming about 98 hours of operation a week. Swapping this 100 watt bulb out for a 9 watt LED bulb would save about a $1.46 per running hour!

This is great. So how long before you are even? In crunching some more numbers and assuming the average price of a existing typical bulb is $.99 and the average price of an typical LED bulb is $3.70 this would equate to about .45 months.

Call it half a month or two weeks. In half a month at 98 hours per week of operation time you are even on swapping the bulb out to a LED in which from there on after you are saving $1.46 per running hour.

Most LED’s are rated for 15,000 running hours. So we are currently even with the cost of the bulb at 1,294 running hours which gives us a minimum life remaining of 13,706 hours. Multiply this by $1.46 saving per hour and for the remaining life of the LED you would save an addition $20,010.

Take note that this is also for just one bulb. Multiply it by how ever many bulbs you are swapping out and the savings is huge. I highly recommend forking over the cash to upgrade all your older bulbs to LED’s, even if they aren’t all at once.

The only thing you need to be careful of is to make sure each bulb has the same color output (2,000 k, or 1500 k…).