How to Install a Light Switch: Step-by-Step Instructions for Wiring Typical Switches

Every house has switches, and more than one. We have all become accustomed to these small devices and consider them an integral part of our everyday life.It may seem that they are all designed the same and are extremely easy to install. However, this is not at all true - the devices are very diverse.

Agree, it would be a good idea for any home craftsman to know which model is best to use and how to install the light switch so that the device works flawlessly.

The article is devoted to solving these issues. We will outline the operational features of different switches, and also provide detailed instructions for installing open, hidden and walk-through models.

Wiring: open or hidden option

Despite the fact that installing a switch may seem like a very simple matter, there are a large number of nuances that a novice electrician must know.

First you need to decide on the type of wiring.

Open wiring is still used in everyday life. It is especially loved by designers who create interiors in retro or loft style.

Electrical wiring is an essential element present in every home.

There are two types of it:

• Open. The wires are laid on top of the wall. They can be secured with decorative rollers or covered with plastic cable ducts.
• Hidden. The wire is laid inside the wall. To do this, channels are cut into its surface into which the cable is laid. After installation, the grooves are sealed with mortar.

Each type of wiring uses a different type of switch. For an open system, choose overhead models that are placed directly on the wall. They are easily recognizable because they are very visible on the surface.

This type of switch was the first to appear and has changed little over the past decades. For closed wiring, internal or built-in models are used.

They are installed in a recess that is previously prepared in the wall. The dimensions of the hole are selected depending on the dimensions of the switch. It is attached inside the recess using special spacer legs.

There is another type of built-in devices - with mounting plates. This option is more convenient to install. After installation, the internal switches practically do not protrude above the wall plane.

Switch wire switching method

Before you begin installing the switch, you need to know that the internal fastenings of the wires in the device may be different. Two switching methods are used.

Screw type clamp

The screw type contact is tightened with a screwdriver. First, approximately 2 cm of the wire is cleared of insulation, then it is located under the terminal and secured. It is extremely important that not a millimeter of insulation remains under the terminal, otherwise it will begin to melt, which is very dangerous.

Screw-type clamps are optimally used for aluminum wires, which tend to heat up and become deformed. To restore functionality, it will be enough to tighten the contact (+)

This connection is especially good for aluminum wires. They heat up during operation, which eventually leads to deformation. In this case, the contact begins to heat up and spark.

To solve the problem, it will be enough to tighten the screw. The wires, sandwiched between two flat contact plates, will “fall into place” and the device will operate without heating or sparking.

Non-screw type clamp

Represents contact with the pressure plate. Equipped with a special button that adjusts the position of the plate. The wire is stripped of 1 cm of insulation, after which it is inserted into the contact hole and clamped. The whole procedure is very quick and easy.

The non-screw clamp is extremely easy to install, which is why experts recommend that novice electricians work with terminals of this type

The design of the terminal ensures high reliability of the resulting connection. Non-screw terminals are best used for copper wiring.

It must be admitted that screw and non-screw clamps provide approximately the same reliability and quality of connections. However, the second option is easier to install. It is this that experienced specialists recommend using for novice electricians.

Main types of switches

The time has long passed when all models were approximately the same and differed only in appearance. Today the manufacturer produces a variety of types of switches. Based on the type of switching on/off, all of them can be divided into several groups.

No. 1: Keyboard type devices

Very simple and reliable design. The basis of the device is a swinging mechanism, which is pressed by a spring. When you press a key, it closes a contact, which turns the electrical device on or off.

For the convenience of consumers, one, two and three-key switches are available. This makes it possible to control not only one, but several lamps at once.

No. 2: Switches or changeover switches

Externally, these devices are indistinguishable from their keyboard counterparts, but their operating principle is completely different. When you press a key, the devices open one electrical circuit and transfer the contact to another.

This allows simultaneous control of lighting from two, three or even more places. Complex circuits that involve more than two switches are supplemented with crossover elements.

Dimmers not only turn on the lighting, but also regulate its intensity. There are also multifunctional types of devices that can simulate presence, operate on a timer, and much more.

#3: Dimmers or Light Intensity Controllers

A switch that allows you to adjust the lighting intensity. The external panel of such a device is equipped with keys, a rotating button or infrared sensors.

The latter option assumes that the device can receive signals from the remote control. Complex dimmers can perform several functions: activate dimming mode, simulate presence, turn off lights at a specified time.

The criteria for selecting a dimmable switch are described in this article.

No. 4: Switches with built-in motion sensor

Devices react to movement. The appearance of people is registered by a sensor that activates the lighting and turns it off if there is no movement. To operate the switch, an infrared sensor is used, which is capable of analyzing the intensity of infrared radiation and distinguishing a person from other objects.

Multifunctional switches with motion sensor capable of not only turning on lighting devices, but also activating video cameras, sirens, etc.

No. 5: Touch-type devices

Turn the lighting off/on by lightly touching the sensor. Varieties are available that are triggered when a hand is passed near their body. The main difference between touch switches and traditional analogues is the presence of microcircuits.

This eliminates the risk of a short circuit, which significantly increases the service life of both the switch itself and the lighting fixture.

There are many types of switches. Illuminated models are designed to facilitate orientation in dark rooms

How to choose the “right” place for the switch

Choosing a place to install the switch is a personal matter for each owner. However, there is a set of industry requirements that regulate this issue. This is due to the fact that laying electrical wiring is quite an expensive undertaking and redoing it every time is expensive and too troublesome.

Experts recommend installing all switches in the house at the same height and the switching position should be common for all.

The devices are usually mounted at the height of door handles, which correlates well with the development of muscle memory. Thus, when entering a room, a person presses a key automatically, without even noticing it.

Another important point: the switch in the room must be positioned so that there is a distance of about 15-20 cm between it and the doorway. This way a person can grab the door handle with one hand and press the key with the other.

For living rooms, it is customary to install switches only indoors. For common areas, such as bathrooms, closets or corridors, switches located outside the room are most often used.

If there are small children in the house, you should not “lift” the switches up. The restless period when the baby will “play around” with the light will pass very quickly, and the inconvenience from the location of the switches will remain for a long time.

The design of the switch is extremely simple. Its main elements: mechanism on the mounting plate, keys and decorative protective panel

General installation diagram of the switching device

Failure to follow basic installation rules, even for such a simple device as a switch, can lead to very unpleasant consequences. These include overheating and sparking with a possible subsequent short circuit, as well as voltage that remains in the wiring.

This is fraught with electric shock, even if you just need to replace the lamp when the lighting is off.

Therefore, before connecting the switch, it is worth remembering the basic connection elements:

• Zero vein. Or, in electrician jargon, zero. Displayed on the lighting fixture.
• Phase diverted to the switch. In order for the lamp to go out and come on, the circuit must be closed within the phase conductor. It is important to remember that when the switching device is brought to zero in the opposite direction, it will work, but the voltage will remain. Therefore, to replace a lamp, for example, you will have to disconnect the room from the power supply.
• Phase diverted to the lamp. When you press the key, the circuit will close or open at the point where the phase channel breaks. This is the name of the section where the phase wire leading to the switch ends and the section stretched to the light bulb begins. Thus, only one wire is connected to the switch, and two to the lamp.

It should be remembered that any connections of conductive areas must be made in the junction box. It is highly undesirable to perform them in a wall or in plastic channels, since complications will certainly arise with the identification and subsequent repair of damaged fragments.

If there is no distribution box near the installation site of the switch, you can extend the neutral and phase from the input panel.

The figure shows a connection diagram for a single-key switch. The places where the wires connect are marked with black dots (+)

All the rules described above apply to a single-key switch. They also apply to multi-key devices with the difference that each key is supplied with a piece of phase wire from the lamp that it will control.

The phase stretched from the distribution box to the switch will always be only one. This statement is also true for multi-key devices.

Replacing a switch or installing it from scratch is carried out only if there is a fully formed electrical circuit.

In order not to make mistakes when working with wiring, you need to know the markings and color of current-carrying channels:

• Brown or white The insulation of the wire is designated as a phase conductor.
• Blue - zero core.
• Green or yellow – grounding.

Installation and further connection are carried out according to these color prompts.In addition, the manufacturer can apply special markings to the wires. All connection points are designated by the letter L and a number.

For example, on a two-key switch the phase input is designated as L3. On the opposite side are the lamp connection points called L1 and L2. Each of them will need to be output to one of the lighting fixtures.

Before installation, the surface-mounted switch is disassembled, and after connecting the wires, the housing is mounted back

Surface Mount Switch Installation Procedure

Such devices are used for open wiring and where for some reason it is impossible to make a hidden connection.

Let's look at the installation procedure using the example of a fully factory-assembled single-key switch. To connect it, you need to turn off the power supply to the apartment, and then perform the following operations sequentially.

Step 1: Disassemble the device

We take a slotted screwdriver, very carefully lift the device key and remove it. After this, just as carefully, trying not to damage it, remove the protective decorative cover. All we have to do is disconnect the working mechanism from the socket plate. Let's carry out this operation.

Step 2: Design the installation location

The manufacturer must make holes on the base plate for securing the device. They need to be marked on the wall. To do this, take the socket box, apply it to the surface and mark the line of the top edge with a pencil.

Using a level, we check that it is horizontal, otherwise we will not be able to install the switch evenly. After this, we again apply the plate to the wall and mark the attachment points.

Step 3: Install the socket plate

Further actions depend on the material from which the wall is made. If it is soft wood, fasten the base with galvanized screws. If the base is made of harder materials, you will have to drill holes in it.

We try to do all the work accurately so that we don’t have to make additional holes. We securely fasten the plate to the wall.

The last stage of mounting a surface-mounted switch is the installation of a protective decorative case and a key. After this, the device can be used

Step 4: Connect the wires

We determine the type of contact switching and cut and strip the wires in strict accordance with it. Necessarily remove all insulationso that it does not subsequently melt and cause malfunctions in the operation of the device.

We check that the wires reach the terminals as accurately as possible; it is undesirable for excess wires to remain. In accordance with the markings and color of the wires, we connect them to the required contacts.

Step 5: Assembling the device

First we need to make sure that the wires are connected correctly, for which we test them with a multimeter screwdriver or other device. Having found out that everything is assembled correctly, we take the switch mechanism and install it in place.

Then we return the protective decorative cover and, last of all, snap the key into place. We check the operation of the device.

Installation instructions for hidden switch

The design of hidden devices differs in the shape of the socket box and the decorative cover. The first is made in the form of a bowl, inside of which the switch mechanism is placed. The lid has the shape of a small panel or even a frame.

Accordingly, the connection diagram for such a switch will be slightly different. Before installation, you need to purchase a socket box, which is sold separately from the switch.

Depending on the material of the walls in which the switch will be mounted, there are two types of socket boxes. The figure shows an option for gypsum plasterboard walls

You need to know that designs for brick and concrete walls are somewhat different from products intended for installation in plasterboard. Be sure to take this into account when purchasing. The hidden switch is installed in the following sequence.

Step 1: Preparing a place for the socket box

The product must be inserted into a pre-prepared niche, the dimensions of which are slightly larger than the socket box. To perform this, you will need a special attachment in the form of a crown for a hammer drill or drill. The diameter of the crown should be slightly larger than the diameter of the socket.

For double switches, two niches are made, which will then need to be connected to each other. A special double socket box will subsequently fit here.

Step 2: Correctly installing the socket box

We de-energize the room. We bring the wires to the installation site of the switch, placing them in grooves prepared in advance. Now you can install a socket box and run the wiring inside it.

For this purpose, there is a special hole in the product body. We fix the structure in place. In concrete or brick we do this using plaster; in drywall we install retaining brackets and secure them with two self-tapping screws, tightened until they stop.

Step 3: Replace the switch

First we disassemble the structure. We take a slotted screwdriver and carefully pry the key with it so that the element can be removed. Then we remove the decorative protective panel. We are left with a mechanism mounted on a metal plate.

Now you need to connect the wires. We measure and cut them. You need to know that in this case it is necessary to leave a small margin of length for each wire.

We clean the ends of the wires and connect them, then we put them inside the socket box and put the switch mechanism in place. Install the mounting plate. Depending on its type, this can be done in two ways: either move the spacers apart and secure them with special screws, or secure them with two self-tapping screws.

After this, we use a tester to check that the device is connected correctly, put on the decorative panel and install the key.

Connecting a pass-through switch

To correctly install a rocker light switch, you need to accurately understand the principle of its operation. In the simplest case, the device, when you press a key, will open one circuit and close another.

On the back of switches of this type, the manufacturer always shows a diagram of the device’s operation. Let's consider the installation procedure for the simplest single-key pass-through switch.

For installation, we will need a three-core cable, each of the cores of which will have a factory color marking. Be sure to turn off the electricity before starting work.

We sequentially perform the following operations:

1. On the pass-through switch we determine the common terminal.
2. We bring out the phase conductor to the switch that is located closer to the distribution box and connect it to the common terminal.
3. We connect the remaining two wires to the output terminals of the pass-through switch. At the same time, be sure to remember what color wire is connected to which terminal.
4. In the distribution box we connect the phase from the lamp with the phase wire of the second pass-through switch.
5. Guided by the color of the braid, we connect the two remaining wires with wires of similar color from the first switch.

Afterwards, we find the grounding and neutral wires in the distribution box and connect them with similar cables going to the lamp.

The figure shows the installation diagram of a simple single-key rocker switch (+)

We carry out all the twisting very carefully, if necessary we tin it and properly insulate all exposed sections of the wires.It is strongly not recommended to connect copper and aluminum wires together.

Next we proceed to installing a pass-through switch, which will be similar to the procedures described above. We disassemble the device, connect the wires to it in accordance with the diagram, put the mechanism in place and fix it.

Reinstall the protective panel and key. Now you can start checking the functionality of the assembled circuit. Make sure that both switches can control the lamp. That is, each device can turn the lamp off or on, regardless of the position of the other device.

Each switching of the pass-through switch must turn the lamp off/on. If not, you should look for and correct the error.

A more complex variation of the single-key rocker switch is two-key device. Essentially, these are two single transition devices assembled in a common housing.

This design allows you to control several lamps at once. The device is connected with a three or six-wire wire.

Conclusions and useful video on the topic

How to install a single-key surface-mounted switch:

Sequence of work when replacing the device:

Rules and sequence for connecting a two-key switch:

Installing and connecting a switch is one of the simplest electrical installation jobs. Special knowledge and skills are practically not required here, but you shouldn’t treat this event irresponsibly either. Electricity does not forgive even the smallest mistakes.

Therefore, those who do not have experience in carrying out such work should seek help from specialists or more experienced home craftsmen.

Do you have practical skills in installing light switches? Share your accumulated knowledge, talk about the nuances of installation and connection, or ask questions on the topic in the comments below.