DIY electrical wiring in the cellar. How to safely make lighting in the basement of a garage and apartment building
To lighting networks located in basements and ground floors special requirements for electrical safety are imposed. Lighting in the basement must be connected to a 36 V network. This is due to the fact that the floor in such rooms is usually earthen, and in the event of an accident there is a high risk of injury to people electric shock. Application protective grounding mandatory in basement lighting networks. Wire connections and any exposed areas, as well as switches, must be located at a sufficient distance from water supply and sewer pipes to prevent water from entering. Cables and individual wires must be laid in protective plastic corrugations or metal sleeves.
A step-down transformer
In the basements of houses old building there is a transformer with an output voltage of 36 V, used for lighting. A cable with a cross-section of at least 5 sq. mm is connected to it through an automatic protective switch, to which wires from lamps and switches are supplied. It is advisable to use copper wire, but the use of aluminum is also allowed. For ease of installation, lamps are connected to the cable not individually, but in groups of 3-6 pieces, connected by a wire of smaller cross-section (to save cable). Such a group usually illuminates a separate corridor, room or passage. All connections are made in junction boxes using terminal clamps.
Installation of a corridor lighting group using terminal clamps
Lighting in the basement of a residential building The structure is much simpler than that of an apartment building. This is due to the significantly smaller area of the basement. To get 36V voltage there are two solutions:
- purchase a small 36 V step-down transformer,
- use ready-made power supplies or autotransformers.
The transformer is connected to the lighting network via automatic protective device. All other requirements for wiring installation are the same as for apartment buildings.
Difavtomat
Lighting in basements at 220 volts is permissible only if there is a concrete floor and it is impossible to install low-voltage lighting. To increase electrical safety, it is necessary to install with an operating current of no more than 30 mA. All wires must be laid in corrugation, and their connections with junction boxes and consumers must be reliably sealed.
Residual current circuit breaker You can do the lighting in the basement yourself. All work must be carried out with the voltage turned off. If possible, it is better to install a step-down transformer in the electrical panel of the house, or make a separate panel for it, also located in the house. If this is not possible or there is not enough space, the transformer is mounted in the basement. In this case, it is necessary to place it as high as possible above the floor to protect it from moisture. It can be installed in a metal panel or on corner brackets, which must be connected by wire to the transformer core and grounded. Circuit breaker It is advisable to mount it nearby so that when an accident is detected, it is possible to quickly turn off the voltage.
Installation option for an electrical panel with a step-down transformer Gross errors when installing electrical wiring
The bare ends are not insulated in any way, are not enclosed in a junction box and are located in close proximity to each other (in the event of a short circuit, there is a high probability of fire) 
It is almost impossible to track the required wire 
The connections are not isolated and are located in close proximity to water pipes(high risk of short circuit and fire)
Various auxiliary premises, which include basements and cellars, require light sources for a comfortable stay in them. Since in most cases natural lighting cannot be provided in the basement, it is necessary to implement it in other ways. And here it is especially important to fully master the topic, to study all its subtleties and nuances. Know what kind of lighting can be used in the basement of a private house and what is required for this. And most importantly, how to make it reliable and safe.
Natural lighting in the basement
Modern materials and technologies make it possible to illuminate the part of the building located below ground level and deprived of access to sunlight, different ways. With the help of special light guides, it will be possible to make the lighting in the cellar as close to natural as possible, and in the literal sense. Special technology transmission of light from the surface in lanterns, called tunnel ones, will tell you how to make lighting in the basement and cellar without wires and electricity. The secret lies in using a combination of two basic elements:
- dome accumulating solar energy;
- channel with reflective walls.
Together they form an effective design - safe, environmentally friendly and, according to experts, efficient enough to seriously compete with electric lamps or LED spotlights.
Artificial basement lighting
Second place rightfully goes to lighting in the basement using electrical sources. But before moving directly to the description of implementation methods, attention should be paid to typical mistakes and miscalculations made when installing lighting in the cellar with your own hands.
Important. Any buildings located below ground level have high air humidity - that is, when in contact with electricity, they are automatically equated to a high-risk group. This requires the use of special closed structures lamps and switches. Otherwise, the health of people in the basement will be constantly in danger.
Rules and requirements for connecting electricity in the cellar
Experts strongly recommend using waterproof low-voltage circuits using step-down transformers - 12 or 36 V, but in no case 220, as in a household network. It is these solutions that are recognized as safe from the point of view of electric shock.
Attention. Electricity requires careful handling, especially in aggressive (humid) environments. Any liquid increases conductivity, and an electric current of only 0.1 A is considered lethal.
It is best to start installing basement lighting for a residential building by installing a power transformer: this is not done in the most utility room, and beyond. Compliance this condition It is necessary to ensure that the wiring in the basement of the building is at low voltage.
To conduct light into the cellar, you will need a double-insulated cable, additionally laid in a special box or metal hose. In the latter case, provision should be made anti-corrosion protection(special coating). The transformer is installed in a moisture-proof shield, which eliminates the possibility of oxidation of contacts and terminals.
Basement lamps must meet several criteria:
- completely cover the lamp with a durable glass cap;
- have a wire casing to protect against mechanical damage;
- avoid (or minimize) contact with parts of the human body.
In conditions low ceilings the latter requirement involves placing light sources on the walls, and not on top.
Safe components
The most reliable and safe electrical fittings are those that were purchased in specialized stores and have all the required protection elements, and are not found in the ruins of spontaneous markets. Before choosing lamps for the cellar, a voltage reduction unit, as well as switches and sockets, you must make the necessary calculations.
You need to pay attention to the amount of electric current in the network and power consumption, and based on them, select equipment. Acceptable use modern lamps on LEDs or LED lights for the basement in a silicone tube: they are characterized by reliability, durability, and efficiency. And they shine brighter ordinary light bulbs and are not much different from them in price. In addition, there are lamps for the basement in 12 versions.
Switches - definitely with high level protection, not regular keyboards. This precaution will save you from unpleasant surprises with a short circuit to the housing and electric shock.
Attention. Installation electrical outlets in basement and cellar conditions is strictly not allowed, since none of them can be absolutely airtight and safe. Failure to comply with this requirement is a direct path to creating a traumatic situation.
Wiring installation
Basic rules for cable installation - use quality components, selected taking into account the likely load. It is determined by calculation, and is taken with a small margin (to avoid overload power units). When installing lighting in basement The cross-section of the wire (it is best to take copper) is also selected a little larger than required.
Any connections should be avoided - with twists, terminals, soldering: than fewer points connecting wiring lines in the basement, the higher the likelihood of its trouble-free operation. Electricians recommend installing a special device for protection against electric shock (RCD) on the switchboard with the transformer. This additional measure will increase the safety of people using electrical wiring and lighting.
Wiring in the basement is carried out with the mains completely de-energized, starting from the installation of fittings and connecting wires. It ends with a connection to a step-down transformer. It would be useful to lay the cable in a sleeve (preferably not subject to corrosion) - the current-carrying conductors must be reliably protected from the influence of the external environment.
Finally
The article describes step by step how to arrange basement lighting. Methods for solving the problem using modern advanced technologies and standard methods are described. A brief explanation is given of which components and equipment can be used and which cannot, and why.
Requirements for connecting electricity are based on ensuring the safety of human life and health. That is why for equipment for basement-type premises, the lighting mode in which is not designed for the constant presence of a person, they will be one, but for use in dry residential premises - somewhat different.
It is hardly permissible to use the same solutions when installing lighting in the basement as for connecting an electric motor or by analogy with the wiring diagram in the garage. And this is the only reason why a cable for a cellar, with equal characteristics (material, cross-section), will cost a little more than a wire for a household network: it uses double insulation.
And one last thing. For those who want to save money on something, for example, on protecting a lamp from moisture, a well-worn quote can be cited as a warning: once a year a stick goes off. And in conditions humid environment any mistake can be fatal, because, ultimately, saving on equipment reliability means saving on your health.
The power supply of a basement or cellar is no less important in their arrangement and operation than ensuring (air exchange in the room).
Mainly the work on power supply of basements or cellars consists of connecting the power cable, installing sockets, switches, lamp sockets and connecting end consumers (devices).
To perform the above work, you will need both mechanical and electric tools:
- Screwdriver Set;
— pliers with insulated handles;
- scissors;
— side cutters with insulated handles;
- hacksaw for metal;
- file;
— mounting chisel for making holes and grooves;
- hammer;
- electric drill;
- nails;
- set of drills;
- electrical tape.
All fastening tools used to supply electricity to premises must be in good working order and easy to use, cutting tools must be sharp and properly sharpened.
Preparation of materials for electrical supply of premises
As a rule, copper or aluminum wires and cables are used for electrical wiring. different sections. Copper wiring is superior to aluminum wiring in many respects, since its main quality is resistance to bending. But nevertheless, it is better to choose one or another material based on what material was used when laying electrical wiring throughout the house, since these two different materials It's better not to combine. Working temperature wiring in rubber insulation should not exceed 60-65 °C, and in plastic - no more than 65-70 °C. And at the junctions of copper and aluminum wires this temperature increases significantly due to the difference in support. Therefore, even if you have to connect them, you must use special connection .
The cross-section of the wires should be selected based on the maximum value of the current that heats the insulation, taking into account the mechanical load on the wires, including in the contact terminals of end devices electrical wiring.
As for laying several wires in special corrugated pipes, the permissible current in them should be reduced by 15–25%, this is due to the fact that they will heat each other. In addition, in hidden wiring channels the cooling conditions are somewhat worse.
The cross-sectional size of the cable cores at low current, especially in screw terminals, is determined mechanical strength conductor. The conductor cable cross-section should not be less than 2.0 mm2 for an aluminum conductor and 1.5 mm2 for a copper conductor. If it is necessary to carry out open wiring on rollers indoors, then the cross-section of the aluminum cable core should not be less than 2.5 mm2.
Probably the main disadvantage of aluminum wires is that they are quite difficult to connect. On the surface of aluminum wires there is a hard and refractory oxide film (it is formed by the reaction of aluminum with atmospheric oxygen) which is a rather poor conductor.
Before connecting aluminum wires, the oxide film must be removed by stripping. However, this is not for long, it forms again, which during soldering prevents adhesion to the solder, and during welding it completely forms undesirable inclusions in the melt.
The oxide film begins to melt only at a temperature of 1500 - 2000 ° C, which is almost 3 times higher than the melting point of aluminum itself. The second in line among the disadvantages of aluminum wire when laying electrical wiring is its low yield strength, which is especially evident with screw terminals. Aluminum wire is squeezed out from under the clamp, thereby weakening the contact.
During operation of the leads, all connections and branches of the wires should not be subject to tension and should be located in places where they can be easily inspected and, if necessary, repaired.
To lay aluminum electrical wiring, it is necessary to use connecting parts with aluminum wires with anti-corrosion galvanic coating. The same requirement applies to steel parts.
To connect the wires, it is necessary to cut off the insulation at their ends. Then the wire is prepared for work (if it is a multi-wire cable core), that is, a dense flagellum is made.
To ensure greater reliability of contact, the cores must be cleaned with fine sandpaper, which is lubricated with Vaseline before use. After that, the end of the core is bent into a ring using pliers or pliers, the diameter of which depends on the diameter of the clamp screw.
The ring must be bent clockwise, this will prevent it from unwinding when tightening the screw. The nut or clamping screw must be tightened until the grower is fully compressed (spring washer).
The connecting material used for soldering is tin-lead solders of the POS-30 or POS-40 type; they differ from each other only in the percentage of tin. Tin-lead solders begin to melt at temperatures of 226 and 235 °C.
For better connection solder to the copper core of the wire, a flux is used, which is rosin, which is usually used in the form of a 20% alcohol solution. Before soldering the wires, their connecting wires are cleaned with fine sandpaper and tinned.
For connection electrical wires there are many ways. But knowledge of all methods of connecting electrical wires when laying wiring in the basement or cellar of a private house is not at all necessary; a few are enough, the main ones of which are presented in the figure below (example in Fig. 158). You can determine the required type of wire twisting in your case based on the material of the wire core and its cross-section. For example, it is advisable to solder aluminum wire strands by first twisting them with a groove.
Rice. 158. Types of wire twisting:
a – parallel; b – sequential
With this connection, under a layer of molten tin-lead solder, the strands of aluminum wires will be protected from the formation of an oxide film on their surface.
To connect large cross-section wires, so-called bandage twisting is used.
For the same purpose, you can use a combination of a bandage twist with a groove. As a rule, the bandage is performed using copper wire with a cross-sectional diameter of their cores from 0.6 to 1.5 mm, which are pre-tinned.
The strands of stranded wires must be stripped, braided and only then twisted (example in Fig. 159).
Rice. 159. Stranding of stranded wires
Wire splicing provides more reliable operation power lines. Therefore, the rules of twisting must be taken with full responsibility.
A simple twisting method involves stripping the ends of a 35-45 mm long steel wire with a fine file or sandpaper, which are twisted tightly.
The remaining ends after twisting are carefully bitten off or filed off with a file, and the outermost turns are tightened with pliers.
Splicing of wires using the bandage twisting method is performed in the following way: the stripped ends of the wires are clamped in a vice and wrapped with soft, pre-stripped and tinned wire.
After connection, the ends of the wires are bent at right angles and 9–11 turns of the bandage are made.
The twist and all adjacent stripped sections of the wires must be protected from corrosion; for this they are coated with special bitumen, asphalt-bitumen varnish, or simply coated with oil paint.
Installation work
There are 2 main types of wiring - internal and external.
Name external electrical wiring It started with the fact that the wires are laid along the outer walls of buildings under awnings and eaves. In this case, the external electrical wiring wires are located in such a way that it is impossible to touch them. It is especially important if the wiring is laid openly along the walls of the building.
Internal wiring is laid inside walls, ceilings, foundations, ceilings, under or removable floors. Hidden wiring can be laid in pipes, flexible metal sleeves, voids building structures, grooves under the plaster.
Important: When installing and adjusting electrical wiring, you must be extremely careful, since non-compliance or violation of safety measures usually leads to severe burns and injuries.
In a room where the relative air humidity does not exceed 55-60%, you can use all existing species wiring.
As for cellars and basements, in these rooms the relative air humidity is usually more than 76%. Therefore, in cellars you can use open or hidden wiring only with insulated protected or unprotected wires located in special pipes.
When installing a hidden installation, pipes and channels are closed along their entire length to a depth of at least 1.0 cm, and wires - to a depth of at least 0.5 cm.
It should be noted that installation of hidden wiring in pipes is more convenient. It is more convenient because in case of repair or replacement of wires they are easy to replace. It is enough to connect the old and new wire, then pull out the old one and thereby lay a new one.
It is also very important to clarify that laying two-wire or three-wire power lines in pipes and channels is not allowed.
The wiring to the lighting fixtures is laid from above through the ceiling, the wiring to the socket and switch is laid indoors from below. At the point where the channels exit the panels and ceilings, wire connection nodes are located in the branch box (example in Fig. 160).
Rice. 160. Connecting wires in a junction box
All ends of the wires are welded, insulated and sealed with cement or gypsum mortar.
Connecting wires in the distribution box
Before proceeding with the installation of electrical wiring, it is necessary to determine the exact installation locations of the group panel, cartridges lighting fixtures and sockets. Then you need to mark the routes for laying the wires, the places where they turn, as well as passages through the walls.
If you are planning installation open wiring, then it is necessary to mark all the places where the wires are attached.
Ceiling lamps are suspended on special metal hooks, which are pre-fixed in the openings of the ceilings (example in Fig. 161).
Rice. 161. Fittings for mounting lamps
Naturally, metal hooks must be insulated from the lamp hangers, and for this you will need plastic or rubber tubes.
According to the standards, horizontal laying of wires is carried out parallel to the line of intersection of the walls and the ceiling at a distance of approximately 10–25 cm.
Electrical lines of plug sockets are laid strictly horizontally, and all descents and ascents of wires to sockets, switches and lamps are laid strictly along vertical line. The wiring along the ceiling is laid with flat wires along the shortest route between the junction box and the lamps. In this case, it is necessary to ensure that the electrical wires do not cross and are not subjected to mechanical stress, stretching or damage.
The distance from parallel electrical wiring lines or from distribution boxes to metal pipelines (water supply or heating) should not be less than 10-15 cm. And if for some reason the wiring line crosses the pipeline, then the distance from it to the pipe at the intersection is not should be less than 6 cm.
To fasten external wiring wires, special plastic fasteners or homemade tin brackets are used, which are tin strips 1.0 cm wide. These strips are attached to the wall using dowel nails.
The wire is attached to the wall at a distance of no more than 40-45 cm. And if the wires intersect, then the attachment points are determined no more than 5-7 cm from the center of the intersection of the wires.
If the wires are fastened to a wooden wall, then the gap between the fastening points should be approximately 30–35 cm. And the distribution boxes in this case are mounted on wooden base using screws.
After marking and measuring the required sections of the wiring, the wires are cut, and it is necessary to leave a small margin at each end of the wire after installation, they will be cut.
The cut wires must be straightened; to do this, simply pull them 2-3 times through a rag held in the palm of your hand. According to preliminary markings or grooves in concrete or brick wall The brackets for fastening the wires are strengthened.
The wires under the metal bracket must be protected with a layer of insulating tape (example in Fig. 162). And in order to be able to reconnect the wires in the junction box in the future, change the socket, switch or socket, and not completely change the wiring section, the ends of the wires inserted into the junction and electrical boxes should have a small margin of approximately 7–8 cm .
The section of wires inserted into the box must be separated, that is, part of the flat dividing base of the wire must be cut out. In this case, it is necessary to ensure that the divided section of the wire does not extend beyond the box.
Rice. 162. Fastening flat wires with metal clamps
The action of moisture in the air on the wire cores leads to their oxidation, which often leads to a break in the contact and disruption of the wiring as a whole.
In order to avoid this, you should carefully insulate the connections, that is, the ends of the wires in the junction boxes. Contact insulation is carried out using electrical tape or other modern liquid insulating materials, which are fused to the ends of the wire strands.
After the ends of the wires are insulated, they are placed in the box in such a way that they do not touch each other under any circumstances, as there is always a risk of something happening short circuit as a result of which the insulating material may be damaged, after which the box is closed with a lid.
When installing wiring open type Switches and sockets of a protected type are installed on plastic, ceramic or wooden sockets pre-fixed to the wall.
The diameter of the socket boxes used should be approximately 1-1.5 cm larger than the dimensions of the devices installed on them.
The technology for laying cables is very similar to the technology for laying conventional wires. But, nevertheless, the conductive wires are attached in a slightly different way.
To fasten light, unarmored cables on walls with two or more conductors, use metal brackets with one leg or brackets with buckles pre-attached to the basement wall (example in Fig. 163).
Rice. 163. Securing cables with various brackets:
1 – with one foot; 2 – with two legs; 3– with buckle.
Accordingly, to lay 2 or more cables in parallel, brackets with two legs are used.
The brackets are attached to stone walls using dowels, and to wooden walls using wood screws. In this case, the cable attachment points should be located at a distance of no more than 45-55 cm from each other.
When turning the power line, the bending radius of the cable should be equal to 10 times its diameter. The first bracket is located 1.5-2.0 cm from the beginning of the cable bend.
Before connecting the cable to a socket or switch, it must be additionally secured to the wall at a distance of approximately 7–11 cm from the entry point and only then installation must be carried out.
When laying electrical wiring in rooms with high humidity, such as a cellar or basement, steel, polyethylene, polypropylene and vinyl plastic pipes and metal flexible hoses (corrugations) are used.
As for the marking of protective pipes, it begins with the location of their ends, suitable for electrical panels, electrical receivers and other control devices. After which the entire route is marked, determining the installation locations of junction boxes, turning angles and attachment points.
Before proceeding with the installation of the pipe, it is necessary to carefully inspect and prepare it, that is, if any damage is detected, these sections must be replaced. After which the metal pipes must be cleaned of all kinds of dirt and rust and painted, if possible, not only on the outside, but also on the inside.
With the use of plastic pipes, a number of problems automatically disappear, for example, there is no need to paint them, and it also allows you to avoid connections in places where the route turns, since plastic pipes bend easily by preheating them in hot water at a water temperature of 100–110 °C, 10-15 minutes is enough.
However, the use of plastic pipes is only permitted in interior spaces, despite the fact that the air temperature in them does not exceed 50-55 ° C. Otherwise, the pipes lose their strength and original shape.
And in order to avoid the accumulation of condensate moisture in the protective pipes, the pipes should be laid with a slight slope in any direction, preferably in the direction where it can flow out freely.
All metal elements of electrical wiring in pipes must be protected from corrosion and. Connecting pipe sections at hidden wiring It is done on a thread with tow and painted over with red lead or oil paint.
Grounding can be done either using a flexible copper jumper from the pipe to the body, or through the pipe using grounding nuts.
Before pulling the wires, it is necessary to check the installed pipeline; to do this, simply blow it with air. Then, if everything is in order and there are no blockages preventing the installation of wiring, pull it into the pipe steel rope with a diameter of 1.5–2.5 mm.
After which the aligned and straightened wires are attached to this cable and pulled through the pipes.
Connecting electrical wires in pipes is strictly prohibited.
Any connections are made in junction boxes and are carefully insulated.
After pulling the wires, it is necessary to check the insulation resistance of the wires between each other and between each wire and the ground. The norm is considered if this value does not exceed 500 kOhm.
Upon completion of the preliminary marking of the points for attaching electrical wires, it is necessary to prepare holes for fastening material and sockets for boxes of electrical installation devices.
Holes in the walls can be drilled or punched using a hammer drill.
The easiest way to break through cinder concrete walls or walls made of red and sand-lime bricks.
To make a hole in concrete wall with granite filler, you will need a special electric car shock-rotational action and cutting tool(perforator) capable of crushing the filler and drilling out the concrete bond.
All sockets and switches with hidden wiring on brick, slag or slag concrete bases are installed in special plastic or ceramic socket boxes. These boxes have two holes for engaging the spacer legs of a socket or switch.
Such boxes can be made independently from roofing iron or tin. Sockets are made for them in the wall using a special crown attachment; if there is no such attachment, first 8-10 mm holes are drilled around the perimeter with a drill, and then the plane of the socket is cut out with a chisel.
If necessary, move the switch or socket, as well as to make narrow grooves in stone wall To embed wires in them at the intersections with pipes (as mentioned above, the distance from the wire to the metal pipe should not be less than 5 cm), a regular chisel or punch is used.
This is what outdoor wiring should look like in a damp room:
Installation of electrical wiring in a corrugated hose
Since the cellar is most often used for storing vegetables and fruits, which natural light begin to deteriorate much faster when used artificial lighting premises. But how to install light into the cellar correctly to protect yourself from high humidity, at which a voltage of 220 V becomes deadly to humans?
Light in the basement
For this purpose, there are special norms and rules that apply to switches, lamps and electrical wiring. Without going into the details of all these rules, we can say that all electrical wiring elements must be reliably protected from exposure to moisture.
Choosing lamps for the cellar
It is very important to choose the right lamps for the cellar, which must meet the following requirements:
- Possess a high-strength lampshade.
- The lampshade must be reliably protected from damage.
- Reliable sealing of the lampshade with the lamp body. The level of protection against moisture must be at least IP 44.
- The luminaire body must be protected from corrosion.
If you use an ordinary light bulb without a lamp for lighting, then over time it will burn out due to exposure to excessive humidity, at best, and at worst, lead to the short circuit of the entire electrical wiring, which is fraught with dangerous consequences for humans.
Lamp NBP 02 60 030 "Corvus" (for CFL 11W, PSH-60, polypropylene body
There are many lamps for sale, differing from each other in price and design. Let's take, for example, the popular lamp NBP 02 60 030 “Corvus”, the body of which is made of polypropylene with an E27 socket with copper contact group, designed for both an ordinary incandescent lamp and an energy-saving one. The light diffuser is made of durable silicate glass and, in some versions, protected by a steel grille. The degree of protection of the lamp from moisture and dust is IP54. Cost – 90 rubles.
Requirements for electrical cables for a cellar
Electrical cables in cellars and basements are subject to high safety requirements. There are two options for electrical wiring: open and hidden. Open electrical wiring should be mounted on insulators at a height of two meters from the floor if the voltage in the network is 42 V and at a distance of 2.5 m if the voltage exceeds 42 V.
Electrical cables for the cellar
At hidden electrical wiring metal pipes with a thickness of at least 2.0 mm are used. The cable is used only with copper conductors in double rubber insulation, impregnated with an anti-rot compound.
For safety reasons, all switches are located outside the cellar.
The installation of electrical wiring in a cellar is not much different in technology from wiring electricity in an ordinary apartment.