Two-key switches are used when you want to connect a lighting device equipped with several bulbs. They allow you to control them from one point, they also help regulate the brightness of the lighting.
Two-key switch device
Design features do not have fundamental differences from single-key electrical devices. The only difference is the presence of two output terminals instead of one. The device also includes the following parts:
- two keys;
- decorative panel and mechanism;
- two output terminals;
- one input terminal.
The terminals are special clamping mechanisms to ensure reliable contact. To commute the wire, you must first strip it and insert it into the terminal strip, clamp it with a clothespin or screw (depends on the modification of the switch). The common or input terminal is, as a rule, separate and has the mark L.
There are two output terminals on the opposite side. They are marked 1,2 or L1, L2. Some models may not be equipped with terminal blocks, but screw terminals. It is not recommended to give preference to them, since the fastening is regularly loosened and it becomes necessary to regularly disassemble the structures and tighten the contacts.
It is necessary to mount the electrical device in such a way that when the lighting is turned on, it is required to press the upper half of the key.
The upper and lower part of the element can be determined using a special indicator screwdriver, which works for short circuit. To do this, take a piece of wire or a nail and touch one contact with it, attach an indicator to the other, holding the thumb at the top on the contact pad. If the light inside does not light up, then the contacts are open. When the position of at least one of the keys is on, it should glow.
Advantages and disadvantages of dual connectivity
It is necessary to start electrical installation activities with the optimization of the operation of all electrical appliances that are combined in one chain.
A good example of an optimized circuit is the traditional organization of lighting the unit in the toilet and bathroom. As a rule, a switch equipped with two keys is mounted in the corridor. One key controls the lighting in the bathroom, and the second in the toilet room.
Installation of a general switch on several rooms is advisable if they are adjacent or located close. For rooms remote from each other, it is recommended to install separate electrical installations.
It is also recommended to install a double switch if the room has a sconce or chandelier equipped with several bulbs. Separate control from one point allows you to expand the functionality of the device and regulate the intensity of combustion.
The installation of a two-gang switch for lighting devices allows to optimize control and adjust the brightness, as well as save energy consumption, installation materials.
Necessary tools and materials
Before you connect 2 switches to 2 bulbs, you need to prepare all the necessary tools and working materials.In order to perform the work efficiently, you also need to study the connection diagram of the double switch. If you know the principle of the device, the circuit can be made independently.
When drawing up the circuit, it is important to consider that only one phase wire must pass through the two-gang switch. Therefore, the neutral and ground wire must be connected directly to the contacts of the light bulbs of the lighting device. It is important to carry out all connections and connections in junction boxes, this is a guarantee of safety in the future.
For work, you will need to have at hand electrical wires with the required cross-sectional area, as well as the switch itself.
From the tools you need to prepare a flat and Phillips screwdriver, side cutters, a mounting knife with a sharp blade and pliers with a level.
Electricians are advised to give preference to well-known manufacturers who are responsible for the quality of the assembly and the material used in the manufacture of tools.
How to connect a double switch to two bulbs
First you need to choose the most suitable place for the switch. There are no legislation requirements for accommodation. Previously, the optimal height was about 2 meters, now the height of the lowered hand of an adult is more often chosen. This allows you to use the switch for almost all residents of the house.
Places where there are certain requirements for the placement of sockets and switches - a bathroom and a bathhouse. The location of the open shower and washbasin is taken into account. Drops of water should not get on the electrical device, or it should have an appropriate degree of protection.
The next step is to complete all the preparatory work. The first step is to de-energize the network, since electricity is dangerous and carries a potential threat to human health and life.
Safety rules when working with electricity:
- disconnect electricity, check the voltage of the indicator screwdriver at the output;
- Do not touch connected electrical equipment with wet or damp hands;
- it is forbidden to use metal staples to fasten electric cables;
- Do not overload the electric network;
- damaged wires are recommended not to be repaired, but replaced with new ones;
- The circuit breaker must be installed using tools with insulated handles.
Getting started, you need to determine the color of the wires. It is used to reduce the time spent on installation work and to create a safe environment.
To ensure proper connection, the following notation applies:
- phase - as a rule, has a red or brown color;
- protection always has one color - yellow-green;
- zero is always blue.
Alphanumeric marking can also be used.
If during the course of the work it turns out that there are no markings, you need to designate the cable yourself using colored insulation or a multi-colored heat shrink tube.
Installation of switches in new buildings is limited to connecting an electrical element to a previously prepared electrical network. In older buildings, where the wiring needs to be modernized or completely replaced, it is additionally required to make new strobes and lay the cable. If an open installation method was used, each wire is fed directly to the switch in special cable channels or insulating corrugated pipes.
Modification of the switches and the installation method used depend on the wiring method. Devices intended for open installation include an insulating decorative cover, an internal mechanism, and a flat socket.The structure is located completely above the surface of the wall, and not in it.
Start by installing a socket. The procedure is carried out using special fasteners. To connect the wires, the switch mechanism is securely fixed and a decorative insulating cover is put on it. Most manufacturers have already thought of a hole for the conductor. The final stage - the cap is put on, hiding the entire internal mechanism, and is securely fixed with latches.
To install a hidden wiring switch, special mounting boxes are used. A small hole is made in the wall. During installation, it is necessary to ensure that the electrical element is installed smoothly and without distortions.
Common mistakes
The most common mistake made by inexperienced electricians is to turn on the switch zero, not the phase, as expected. The switch during operation must break the phase conductor, but in no case zero. If you neglect this rule, the base in the lighting device will always remain energized and elementary replacement of the bulb can cause serious injuries.
Another common mistake is that inexperienced specialists start the phase conductor not on the common terminal block of the switch, but on one of the days off. In this case, the circuit will be inoperative. The bulbs will light up only when both keys are simultaneously on.
If people drove into a rented apartment or purchased a new living space, and lighting fixtures behave unpredictably, most likely, the wrong installation of power cables was made. It is necessary to disassemble the switch and check whether the connection scheme of the two-key switch for two bulbs is correctly implemented.
If there are difficulties with self-installation, you can contact the electrician in private or visit the housing office / distribution / management company and leave a request.
