LED strip is a printed circuit board in the form of a flexible strip. Along it are two, and on RGB devices – four conductive strips (on RGBW strips – five), between which the LEDs are located. In devices connected to 12 V, they are assembled in groups of three diodes and a current-limiting resistor.
The number of diodes depends on the supply voltage, and if the supply voltage is higher – 24, 110 or 220 V – there are more LEDs in the group.
Where the roll can be cut, there are contact pads on the conductive strips to connect the wires. There are also markings there for where to cut – a dotted line or scissors.
How to Cut a Normal 12V LED Strip
On a 12V LED strip, the diodes are arranged in groups of three. Between each group there is a cutting point marked with a corresponding icon.
This is where it can be cut into pieces. If you cut it arbitrarily, the LEDs closest to the cutting point will not light up and there will be no place on the conductive layer to connect. In this case, you will have to shorten the strip and cut off the damaged section.
How to Cut a Colored (RGB) LED Strip
The device RGB strip is similar to the usual strip. The main difference is that it has four conductive strips. They are marked with the symbols “R”, “G”, “B” and “-“. This distinguishes them from the normal strip, on which the contact pads are marked with “+” and “-“.
It can be cut in the same way as a regular monochrome strip – at the cutting point marked with the corresponding icon.
In addition to RGB devices, there are RGBW, with five current-carrying strips and LEDs of four colors – red, green, blue and white. They cut the same way as the regular, monochrome ones.
If the LED strip to improve waterproofness is applied a layer of silicone, only on top or both sides, it is cut as usual. The device of such a design with LEDs is no different from the usual.
The main difficulty is that when cutting the silicone does not interfere with this operation exactly in the middle of the contact pad. Therefore it is better to do it not with scissors, but with a sharp knife:
- cut the top layer of silicone in the intended place;
- cut the strip itself;
- cut the bottom layer of silicone.
After cutting the piece to the desired length, it is necessary to trim the ends of the strip for soldering or connecting the connector. This is done with a knife. To solder the wire, it is enough to remove the silicone only from the top. To connect with a connector, the bottom layer of silicone must also be removed.
Cutting the LED Strip for Repair
During operation, one of the diodes can fail. This will lead to the fact that the whole group will go out – three in a device designed for 12 V or more, in devices that are connected to a different voltage. To repair it is necessary to cut out the damaged section and replace it with a serviceable one. Such a band is cut at the cutting points near the non-functioning LEDs.
If There is no Marking
If there is no marking of the place of the cut, it is made between the adjacent contact pads or in the middle of the pad extending along the conductive layer.
This pad looks like an extension of the strip on the edge of the tape and should be on all the strips that are on the device.
They are located next to each other, across the strip with LEDs.
Connect the LED Strips Correctly
Connect the cut sections can be using soldering or connectors.
Connectors allow you to connect the wires at the site of installation, as well as to make its repair without disassembly.
Wires for soldering need a cross-section up to 0.5 mm2.
It is better to choose a soldering iron with power up to 25W. A more powerful one can overheat the contact pads and they will come off the base.