The comfort of living consists of many components, among which an important place is occupied by the management of the lighting system. It can be made more convenient by installing two-key electrical appliances.
Agree, it would be nice to learn how to carry out such work yourself, especially if there is a major overhaul of housing and updating the wiring. But before you connect a double switch to two bulbs, you need to decide on the circuit and study the procedure.
We will help you implement your plan. The article describes the nuances of implementing different connection schemes, as well as provides step-by-step instruction for installing a two-key switch. The text material is supplemented by visual illustrations and video reviews.
Pros and cons of dual connectivity
An experienced electrician begins any project to improve the lighting system by optimizing the use of all electrical devices combined in one chain.
An example of an optimized circuit is the traditional lighting arrangement of the toilet + bathroom unit. On the corridor side, one switch is usually installed, but with two keys.
Thus, the lamp in the bathroom is controlled by one key, and the lamp in the toilet is controlled by the second. With one movement of the hand, you can perform two actions at once, turning off the light in one room and turning on the lighting in the next one, which is very convenient.
If the switch is installed in the wall between the two parts of the bathroom, then choosing a key is not difficult - it will be located on the side of the desired room
Installing a general switch in two rooms is advisable if they are nearby. For remote rooms, it is reasonable to use separate electrical installations.
A double switch may be required when installing a chandelier or sconce with two bulbs. Separate control expands the functionality of the lighting device and allows you to increase or decrease the intensity of combustion.
If you use one key, then the lighting will be inferior, when you press both keys, it becomes twice as bright.
In order to save energy, it is not necessary to operate both bulbs at the same time. To create an atmosphere of relaxation, just turn on only one of them
As you can see, the ability to connect a double switch to two separate bulbs makes it easy to control lighting fixtures or adjust the light intensity. When installing a single device in two rooms, not only electricity is saved, but the number of installation materials and devices is reduced.
How to choose a scheme for two bulbs
There are differences in connecting the 1-key and 2-key switches. To better understand the difference, first consider the installation nuances of a single-keyboard.
One or several light bulbs can be connected to a conventional switch with a single key - the principle will remain the same.
The diagram shows a variant using a two-core cable, without using "ground". The zero core is pulled directly to the lighting device, and the phase is led to the switch, from where it goes to the bulbs (+)
This is the simplest scheme, it is traditionally used if you need simple control of the lamp or the whole group. When you turn on the electrical system, all involved light sources light up. If a chandelier or sconce with two lamps, then both will turn on at once, one of them will not be possible to use the opportunities.
Now, let's consider what changes if a single-key device is replaced by a two-key. The first scheme for connecting a double switch to two separate bulbs is relevant for the TN-C system, which is still found in old houses. Two-wire wires are used for the lighting circuit.
Zero through the distribution box goes directly to the lamps connected in series, and the phase goes to the input terminal of the switch. But the output is already double: from each of the output terminals the phase conductor to a separate lamp (+) leaves
It turns out that you can simultaneously use either one or both light bulbs, using either one or two keys.
A positive point is the ability to change the lighting intensity in one room. If the lamps are in different rooms, respectively, you can turn on the lights in each room individually or both at once.
In new homes, different grounding systems, for example, TN-S, are used. The difference between the second scheme for the home electrical network is that a three-wire wire is required: the third core is the "ground".
Like the zero core, the ground wire is sent to the switch box, and then connected to the wires of the lamps and connected to the metal parts (+)
The ground wire is connected differently if there is a socket in the same unit with the switch. Then the "earth" from the switchboard reaches for the distribution box, and from there - to the outlet.
Step-by-step installation instructions
Conditionally connecting a switching device can be divided into several stages. Start with the cables: if the wiring is old, then it must necessarily be replaced.
Then it is necessary to correctly connect the wires in the junction box, and finally, in the switch mechanism. For installation of a chandelier or lamp, the instructions suggested by the manufacturer are usually used.
Stage # 1 - Preparing Walls
It is recommended to skip the wall gating stage only if a new wiring with copper conductors of a suitable section has already been laid. When in doubt, it is best to consult an electrician.
For the lighting group, a normal VVGng wire with a cross section of 1.5 mm² is suitable. If sockets are connected with the lighting, it is better to immediately take the same wire, but 2.5 mm².
The preparation of the walls includes gating, arrangement of installation sites for socket boxes and distribution boxes. At the same stage, you can install an additional circuit breaker in the switchboard.
A separate protective device will come in handy when the lighting line needs repair - you can turn off only one circuit, the rest will work in normal mode.
The strobes are knocked out with a puncher, a circular tool and even manually, however, to cut out even grooves, they use a special tool - a chaser, equipped with a vacuum cleaner
The lighting system of a wooden house is different type of wiring. The hidden method is not used, since it is extremely fire hazard and requires maximum cable insulation.
Wires are mounted on the outside, on special insulators. Overheads are installed instead of internal switches, but the principle of connecting the cores to the terminals does not change.
At the end of the chipping of concrete, brick, aerated concrete walls, the grooves into which the wires are laid are covered with a building mixture or alabaster. Then you can plaster and decorate the walls, but the location of the wires is better to keep on the drawing or diagram - until the next repair.
Stage # 2 - connection in the distribution box
A junction box is a chamber where wiring and connection of conductors takes place. When installing switches or sockets of various types, the wiring diagram changes.
But first you need to choose the right junction box. Previously, metal products were used, now they produce safer and more convenient plastic analogues in installation.
There are internal and external models, but it’s always easier to work and work faster with external ones. If urgent wiring is required due to the replacement of the electrical installation, then to access the built-in distribution box, you will have to dismantle the plaster, and then make repairs.
The case of the external model is always in sight: just unscrew the cover and carry out the necessary actions.
The connection diagram of the cores is simple: the zero wire from the shield is twisted with the zeros of the two connected lamps, and the phase goes to the switch. Two output phases from the switch go to the lamps - one for each
If the wire is three-core - and now it is most often used - then in the distribution box, similarly to the zero core, there is a twisting of the "ground". And if the wiring is old, but reliable, then there is no reason to change it, and you need to use the connection indicated on the schematic image.
There are several ways to connect wires. The most common are twisting followed by isolation and the use of terminals.
Soldering is extremely rare. If you are used to using terminal blocks, then you can consider the option of a distribution box with pre-installed terminals.
Stage # 3 - installation of fixtures
How to install a chandelier with two lamps or two separate lamps depends on many factors:
- models of the lighting device;
- readiness wiring;
- basis for installation.
The easiest way to change lighting equipment when the wire is routed to the installation location, for example, in the center of the room.
To install the chandelier, you must perform two operations: hang the light on a hook or bracket and connect the wires correctly
If the ceiling is new and is a suspended structure (suspended, plastic or plasterboard), then for mounting the chandelier, additional fixtures or embedded ones should be installed.
When two phase wires are fed from the two-key to the lamp, they are connected in turn - each to its own lamp. Also, two zero conductors are stretched from the distribution box - they are also scattered over different lamps.
If both bulbs are connected to the same wire, they will turn on / off at the same time, and it makes no sense to install a double switch.
When installing two separate lamps in different rooms, the connection principle remains the same, only the wire feed from the distribution box is changed - they are sent in different directions. As a rule, rooms are in the neighborhood. It is better to mount the switchgear above the switch, about 15-20 cm from the ceiling.
Stage # 4 - Installation of the switch
There are no difficulties either in the installation or in the connection of the two-keyboard. It is installed in the socket or directly into the wall, fixed with paws or screw connection. How wires are connected is shown in the photo.
The double switch is always connected only to the phase conductor coming from the switch box, where it gets from the electrical panel. The core is inserted into the terminal labeled “phase L”. From the output contacts L1 and L2, the phase conductors go to the lamps (+)
If the chandelier has not two, but more lamps, which is much more common, then the connection is made in groups. All lamps are divided into two equivalent or unequal groups, and then the wire from pin L1 goes to one, and the wire from contact L2 to the second.
Conditional division into groups is carried out depending on the desired degree of illumination of the room. If you need two intensity modes, weak and bright, then you can bring the first core to one lamp, and the second to the others. To reach the maximum brightness level, just press both keys.
General recommendations and tips
There are several important points that should not be forgotten. They relate to both installation work and equipment selection.
The implementation of simple rules will make the system more secure and reliable, which is important for a closed network.
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All work on connecting electrical equipment in the switchboard is carried out by qualified electricians serving the house. Interfering with the security system located on the site is not recommended
For the external type of wiring, special materials are used: a cable in strong insulation, ceramic rollers on which it is mounted, and an overhead switch. Products from the same collection look more aesthetically pleasing
If it is not possible to rent a chipper, then the grooves can be cut with a circular, but this is a difficult and time-consuming task. To ensure that the strobes are even, it is recommended that you make an accurate marking on the walls
For accurate installation of switches, socket outlets are used, as for sockets. These are polymer boxes made of non-combustible material, which must be fixed in a wall hole. Installation is carried out on fasteners, gaps are covered with alabaster
To ensure their own safety, it is necessary to use insulated screwdrivers and pliers during electrical installation, as well as special gloves and voltage measuring devices in electrical installations - testers and indicators
To twist or insert wires into the terminals, the ends of the cores must be freed from the insulating sheath - cleaned. To do this, use a sharp clerical or construction knife, as well as special pliers - stripper
Traditionally, color marking is used to indicate the load of cores: phase - red, brown, black; zero - blue or blue-white; earth is green or yellow-green. However, the installed wires may be mixed up, so a double check is necessary.
Junction boxes and socket boxes have limited internal space, so it is necessary to cut off excess wires. However, you should always leave a small margin for subsequent replacement of electrical equipment or reconnection.
Mounting the circuit breaker in the shield
Installation of outdoor wiring in a wooden house
Strob Cutting Tool
Switch hole equipment
Tool for electrical work
How is wire stripping
Color coding for conductors
Wire length in boxes
Do not forget that any actions with electrical appliances and installations are carried out only after a power outage on the apartment panel. Before each operation with wires, make sure that the circuit is de-energized.
If, instead of the usual two-key, you want to install a proximity switch or a device with a dimmer, be sure to study the circuit, as the installation of such devices may vary.
How to properly wire the wires and install the devices is best imagined by watching the training video.
Two-button on two lamps:
Nuances of connecting a chandelier:
Useful connection tips:
The procedure for installing and connecting a double switch can be performed without involving a qualified master, however, during work, you should remember the safety rules. Before electrical work, it is necessary to consider all factors and choose the right scheme.
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