The number of household appliances, digital gadgets and other consumers of electricity is steadily growing year by year. However, the number of outlets for connecting them in our homes is relatively small. The use of tees and extension cords does not meet the requirements of electrical and fire safety. The most inexpensive and safe way out of this situation is to install an external outlet. Also, such sockets are necessary in houses with external wiring or, if necessary, transfer them to another place.
Outlet Design
Unlike an outlet for indoor installation, fixed in a wall socket mounted on a wall or partition, an external outlet is mounted on the plane of the wall. Its design consists of a group of contacts mounted directly on the wall, and a plastic case covering the mechanism of electrical contacts. In some products, a plastic socket is provided for the contact mechanism, which closes the shell of the case.
Main characteristics
- The maximum current. In practice, products on 6A, 10A and 16A are used. Products for current 6 and 10A are rarely used, because modern electrical appliances consume great power. Sockets at 16A are guaranteed to allow you to connect any household appliance, including an electric kettle, a washing machine, etc.
- Rated voltage. In our country, the voltage in the mains is 220V AC.
- Degree of protection against dust and water. To ensure a high degree of protection, an outdoor outlet with a cover is used.
- Geometrical sizes.
Contact Module Mechanism
The contact group of the outlet performs its main function - the transmission of electric current from a stationary electrical wiring to the plug of an electrical appliance. It consists of a base that holds the contacts themselves, and terminals for connecting wiring.
The base is made of plastic or ceramic. The ceramic module has high heat resistance, is non-combustible, but quite expensive and fragile, and is rarely used at present. Plastic products are durable, high electrical insulation properties, resistant to high temperatures and are currently the most common. Installation of an external outlet is carried out by fixing the base to the wall; for this, special holes for screws are provided in the module.
Contacts are made of sheet brass or nickel-plated brass. Nickel-plated contacts are less susceptible to oxidation and provide better electrical contact, which reduces their heating at high currents. In some products, the contacts are preloaded by an additional spring, which also improves the quality of the connection.
Terminals for connecting stationary wires can be screw or quick-clamp. As a rule, they are designed to connect wires with a cross section of up to 2.5 mm square. Usually, the socket terminals allow you to connect two wires per pole, which allows you to use the sockets as pass-through. In some products, only one wire per pole is allowed, such products cannot be used as pass-throughs. To connect a loop to each such outlet, you need to make a separate branch.
Ground contact
Many buyers of wiring products have a choice: which outlet to buy - with or without grounding contact? Protective grounding is designed to disconnect the appliance when its insulation fails, for example, when any wire inside the washing machine is shorted to its metal casing. The body of the machine in this case can be under dangerous voltage. All new electrical wiring is carried out in a three-wire circuit, and many old networks, too. An external outlet with grounding is not much more expensive, and the level of protection is much higher. In addition, its mechanism has a greater depth and holds the fork more reliably.
Socket housing
The housing prevents contact with live parts and, in case of fire, limits the spread of fire. Therefore, the highest demands are made on the material for its manufacture; it must be heat-resistant, shockproof, not emit toxic substances during combustion, and be a good insulator. As a rule, PVC or ABS plastic meets these requirements. If the outdoor outlet is used with open wiring, then the input wire is inserted through the side wall of the housing. To accurately and accurately cut a hole of the required size, special markings are cast on the inside of the case.
Degree of protection
Often outdoor outlets are mounted in humid, dusty rooms or even outdoors. The cases of such products are subject to special requirements for moisture and dust protection. The ability to protect the mechanism from the external environment is indicated by two Latin letters IP and two numbers, the first of which describes the degree of protection against solid particles, the second - from water. For example, IP21 is a product with protection against particles of 12.5 mm in size and drops of water falling vertically (room socket). For rooms with wet processes, IP44 degree - protection against particles of at least 1 mm and water splashes, contacts are protected by a cover. Outdoor socket dust and water tight with grounding, degree IP54 - protection against dust and water splashes. When using such products, it is important to ensure the tightness of the cable entry. To do this, the moisture-proof enclosures are equipped with gaskets to prevent moisture from getting inside.
Open wiring
Despite the high requirements for decoration, open wiring retains its position. It is especially relevant in office buildings where it is necessary to dynamically change the configuration of workplaces. Also, often the open laying of cable lines is used in low-rise buildings, cottage construction and, of course, in the repair of existing electrical wiring. The most effective and aesthetically attractive way of open wiring is laying in plastic cable ducts. Manufacturers of electrical products produce a line of wiring products compatible with cable channels. Products such as Legrand sockets easily fit into cable channels without a visible connection.
Outlet block
The installation of internal outlets requires the installation of sockets for sockets, which is associated with the need to use a hammer, noise and dust. In addition, punching several nests in one section of the wall can weaken the supporting structure. None of this is required but the installation of overhead wiring products. Therefore, outdoor sockets can be mounted in blocks. The outdoor outlet block consists of several modules with contacts installed in one housing. Sockets in one case are mounted in one row (up to four pieces) or a matrix. For example, Legrand sockets can be installed in a 2x3 unit, and some switches can also occupy a part of the housing. The advantage of this design is the ease of installation and aesthetic completeness of the unit.
Outlet Installation
Installing an external outlet is not particularly difficult and is available to anyone who has minimal skills in working with hand tools and electrical safety.
- The purchased wiring product must be disassembled.
- Attach the contact block (or the back cover) to the wall, align it horizontally and outline the mounting holes (usually 2, but more may be required for the block).
- Depending on the material of the wall, drill holes with a drill or puncher according to the marks.
- Install dowels in the drilled holes.
- Attach the contact block and fix it with self-tapping screws. If the module is ceramic, it is important not to overtighten, because the ceramic can easily crack.
- If you are installing an external outlet on a wooden wall, you must use a wall socket made of non-combustible material.
- Lead the electrical cable to the outlet and separate it, exposing 10 mm of each core.
- Depending on the type of terminal, either tighten the ends of the wires with screws or push them into the holes of the self-clamping terminals.
- If the outlet is straight through, also separate and connect the outgoing cable.
- Depending on the design of the cover, cut a hole for the cable entry in its side wall. In case the cable entry of the socket is tight, it is necessary to install a standard gland on the cable before terminating it.
- Install and lock the cover.
The installation of the external outlet is completed, it remains only to check its operability.
Modular products
Separately, mention should be made of modular sockets. Their filling consists of inserts of one standard size. At the same time, their functional purpose may be different: switch, 250V socket, external television or computer socket. Some modules are made in half size and are installed in two pieces in one socket, for example, telephone and computer ports. The modules are installed in the housing horizontally or vertically, up to 6 pieces, or in an array of 2x3, 2x3, 2x4 pieces. Most often, such products are used in the office wiring device.