If you’re looking to add color or subtlety to a room, LEDs are a great choice. LEDs come in big rolls that

you can easily set up even if you don’t have any electrical experience. A successful installation just takes a

little bit of planning at first to ensure you get the right length of LEDs and a power supply to match. Then,

you can connect the LEDs with purchased connectors or by soldering them together. Connectors are

easier to use, but soldering is the better option for a more permanent way to join LED strips and

connectors. Finish by sticking the LEDs in place through their adhesive backing, then plug them in to

enjoy the ambiance they create.

1/Selecting LEDs and Power Supplies

1/Measure the area where you plan on hanging the LEDs.

Take a rough estimate of how much LED lighting you’re going to need. If you’re going to install LED

lighting in different locations, measure each spot so you are able to cut the lighting to size later. Add the

measurements together to estimate the total length of LED lighting you will need to purchase.[1]

Plan out the installation before doing anything else. Try making a sketch of the area, noting where you’re

going to place the lights and any nearby outlets you can connect them to.

Be sure to account for the distance between the nearest outlet and the LED light location. Get a longer

length of lighting or an extension cord as needed to fill in the gap.

LED strips and other supplies are available online. Some department stores, home improvement centers,

and light fixture retailers also carry them.

2/Check the LEDs to see what kind of voltage they require.

Look at the product label on the LED strips or on the website if you’re purchasing them online. LEDs are

either 12V or 24V. To keep your LEDs running long-term, you have to have a matching power supply.

Otherwise, the LEDs won’t have enough power to operate.[2]

If you’re planning on using multiple strips or cutting LEDs into smaller strips, you can generally wire them

to the same power source.

The 12V lights are fit well in most locations and use less power. However, the 24V variety shines brighter

and comes in longer lengths.

3/Determine the maximum power consumption of the LED strips.

Each LED light strip consumes a specific amount of wattage, or electrical power. It depends on how long

the strip is. Check the product label to see how many watts per 1 ft (0.30 m) the lighting uses. Then,

multiply the watts by the total distance of the strip you plan on installing.[3]

For example, if you’re installing a 25 ft (7.6 m) length of lighting that requires 5.12 watts per foot: 25

watts x 3 ft = 128 watts total.

Remember that the measurement will vary depending on where you live. Check carefully to see if it’s

watts per meter or watts per foot.

If the product label lists the total wattage, divide it by the total number of feet or meters in the reel. For

example, if the strip is 5 ft (1.5 m) long at 24-watts: 24 / 5 = 4.8 watts per foot.

4/Multiply the power consumption by 1.2 to figure out the minimum power rating.

The result will tell you how strong your power supply has to be in order to keep the LEDs

powered. Since the LEDs may use a little more power than you anticipate, add an extra 20

percent to the total and treat it as your minimum. That way, the power available will never

dip below what the LEDs require.[4]

For example, using a 25 ft (7.6 m) strip: 128 total watts x 1.2 = 153.6 watts. The power

supply should offer at least 153.6 watts, or else the lights won’t work.

Add 20% to the estimate to ensure the lights stay on: 153.6 watts x 20% = 30.72 watts.

Then, 153.6 watts + 30.72 watts = 184.32 total watts.

Many online retailers have a handy calculator you can take advantage of to ensure you get a

compatible power supply.

5/Divide the power consumption by the voltage to get the minimum amperes.

One last measurement is essential to powering your new LED strips. Amperes, or amps, measures how

fast an electrical current travels. If the current doesn’t travel fast enough through a long stretch of LED

strips, then the lights will dim or shut off. The amp rating can be tested with a multimeter or estimated

with a little math.[5]

For example, if you have 12V LEDs that use 128 watts of power: 128 / 12 = 10.66 amps.

To test LED strips, touch the multimeter’s leads to the LED’s copper dots. Make sure it is set to A for

amps.

6/Purchase a power supply that matches your power requirements.

You now have enough information to select the perfect power supply to light up the LEDs.

Find a suitable power supply matching both the maximum power rating in watts and the

amperage you calculated earlier. The most common type of power supply is a brick-style

adapter, similar to the ones used to power laptops. It’s very easy to use, since all you do is

plug it into the wall after connecting it to the LED strip. Most modern adapters come with

the parts needed to connect them to LED strips.[6]

If you’re planning on powering different LED strips separately, get power supply adapters

for each one. Remember to calculate each one’s power requirement, since they may be

different.

If you have dimmable lights, select a power supply that is also dimmable. You could also

place a dimmer switch between the power supply and the LEDs.