Cutting and connecting LED strips: an easy task
LED strips are a very interesting light alternative because they can be used on several fronts. Generally their use is decorative, although they are being increasingly used as supplementary lighting points or as the main light. Flexible, rigid, mono-chromatic or RGB there are many types of strips accesible in the market.
Before making any deeper descriptions, is good to know the four main ranges of voltage to which an LED strip can operate:
- 5 VDC LED strips: not very common. They can be either digital or analogical and they are generally connected to a USB port.
- 12/24 VDC LED strips: undoubtedly, the most used. They require knowing the process of cutting and and joining different stretches of strip, but the great advantage is that you can make precise installations and somewhat more elaborate, tailored to what each project needs. The great disadvantage, if it can be called that, is that they require a transformer to convert the current that pours from the electrical network to the working voltage of the strips.
- 220 VAC LED strips: Due to their IP65 protection rating they are mostly intended for outdoor lighting. They are perfect to highlight specific points in a garden, for example. They don’t require a transformer, so they are easier to install.
Procedure to cut and join 12/24 V LED strips
The steps you will have to follow to cut and join different stretches of 12/24 LED strips are not complex and, as we have mentioned before, they are also safer to undertake than those of other installations. But it is necessary to execute them with attention and care:
- Calculate and cut the stretch (only if you need to cut) of LED strip that you need. If you are going to make a cut remember that, as a rule, 12VDC strips can be cut every 5 cm and 10 cm if they are 24VDC. Generally, it is clearly indicated where the separation can be made.
- It is necessary to make sure that the profile where the LED strip will be installed is clean. Although it is not mandatory using a profile, it is highly recommended that the LED strips are installed in this type of pieces, eliminating the temptation to place them directly on wood or plaster.
- Connect the strip to the corresponding transformer following the instructions. You will need two wires (red and black) that you will connect to the symbol + (+V) or - (-V) respectively. Subsequently you must connect the power source to the electrical network.
Are you going to join several stretches of 12V LED strips?
- The cut must respect the sections indicated for each type of LED strip.
- The union of the different stretches can be managed through rigid connectors or connection wires. The rigid ones are safer and they allow the joints to generate a straight line, a right angle or even more complex installations in a T shape.
- Stick the LED strip to the corresponding profile and connect it to the transformer and, then, to the electrical network.
Although12V and 24V LED strips can be cut and joined without problems, always following the instructions, it is recommended that any installation of this type does not exceed 10 and 15 meters respectively in order to avoid unexpected voltage drops.
220v LED strips: a somewhat more special case
These strips are a “modified” version of the previous ones. Their main advantage is that they can be connected directly to the network, making the installation much easier, since it avoids having to depend on transformers (a key component in the case of 12/24V LED strips). This type of strips can extend up to 50 meters without voltage drops.
More details about the installation of 220V LED strips :
- They are available in 50 or 100 meter coils. Another big difference with regard to other similar lighting systems is that you can only cut every 1 meter. If this measure is not respected, the strip will not work.
- Stretches can be joined and still be used simply by welding the connection wires to the split end.
- Always start introducing the 4-pin connector in the LED strip. These connectors have two distinct parts: pointed spikes and rounded spikes. The first ones must coincide with the aluminum sheets, while the second ones will be introduced in the plug/connector. Once all the elements are connected, you just have to plug in the strip.
- In case the strip does not start to light up, we advise you to the check proposed in this post
- Finally, note that the IP rating of the 220V LED strips is IP65, so they can be used to light outdoor spaces and with decorative intentions.
How many LEDs per meter are necessary?
It may seem a trivial detail, but the amount of LEDs per meter directly affects the brightness and power consumption. For this reason, before undertaking the installation it is important to decide the objective of lighting in order to choose between the different types of strips. These tips will help you choose correctly:
- 30 LEDs/meter: intended for auxiliary lighting and tenuously highlighting specific elements (a table, a tree, the profile of a mirror from the back...)
- 60 LEDs/meter: for standard lighting. It’s the perfect amount to ingrate in moldings, corridors or bar bars
- 120 LEDs/meter: for very high lighting requirements. Specially useful for outdoor lighting.