- We draw up a plan for the location of the wiring
- Tools and materials for work
- Sequence of work
- Wire laying, connection to the board
Your apartment is already in need of renovation. The first question is: what can you do yourself? Let’s talk about self-replacement of electrical wiring, about the nuances and methods of performing electrical work.
Determine exactly what you want to get as a result of the repair, what electrical appliances will be used, where they will be. If you intend to install new cabinet furniture – you should not hide the socket and the switch behind it, you will not be able to use these products. The more accurately you calculate the number of electrical receivers, the less extension cords will have to be installed. Electrical equipment in the toilet and bathroom must be connected to splash-proof sockets. A three-core wire in a corrugated PVC pipe will be routed to the outlets. If you think that it is necessary to install a shield with protection devices in the apartment, think about where it will be located, how to bring the wires to it. The wire must be laid with a three-core copper. The choice of wire cross-section depends on the load expected at the connection points. It is best to use the sockets of the German standard with a protective contact. They are good in that the protective contact comes into contact earlier than the conductive contacts.
Note that often walls already have conduits for wires and openings for sockets and switches. They are simply sealed with mortar. Tap the walls, maybe there are such places. When using old channels and trays for laying wires, the volume of work will decrease, the bearing capacity of the walls will be fully preserved.
Before starting work, it is necessary to clearly determine what you will do yourself, and what an electrician should do. All installation and dismantling work in the switchboard on the landing, on the wiring section from the switchboard to the first box in the apartment, in this box, should be performed only by an electrician. Failure to do so can result in electric shock, damage to the general board and damage to your neighbors’ wiring..
We draw up a plan for the location of the wiring
Make a plan for the location of the wiring, display on the diagram. During work, follow this plan. If you need to change the location of the network elements – make these changes to the diagram. Snap all sizes to corners, niches, etc. Maintain a plan in case of home improvement and home improvement work. The wires to the sockets and switches should fit in vertical lines from their connection points at the top of the walls. Wall-to-wall wires run in floor slabs. The direction of the wiring is determined at the connection points of the luminaires. When outlining lines for wiring, follow the PUE in paragraphs 7.1.46–7.1.52. To select the cross-section of the conductors of the wires, see table 1.3.4 there. Please note that the distance to outlets and switches is measured from a clean floor. When installing an additional outlet, do not install an extra junction box. It is more rational to use the box, which is located above the nearest outlet on the same wall, to make a connection in it.
Reinforced concrete walls are reinforced with mounting elements. These elements are in the form of grids and lattices. The reinforcement is positioned approximately 15 mm deep from the wall surface. In brick walls, reinforcement is carried out with nets. A depth of 15 mm is sufficient for making furrows on the wall surface. Another thing is punching a recess for installing a socket. In this case, it is not worth cutting the reinforcement – weaken the wall, extra work. Pre-inspect the installation site of the outlet or switch using drilling. If you get into the reinforcement, move the product installation point a little. Start by preparing the places for the outlets, then mark the grooves to the ceiling.
Tools and materials for work
To make grooves and grooves for sockets, you will need tools:
- Perforator. If you have to perform a small amount of work, you should not buy a rock drill with a power of more than 1-1.4 kW. It is designed for harsh operating conditions, has more weight, and its cost is higher. All you need is a hammer drill of the above power, which has a smooth speed control and a switch for working in drill mode. These hammer drills usually have a chuck with cam clamps for conventional drills, as well as lance, chisel and drills of different diameters..
- Drills for concrete, crown. Rock drill accessory tools must have SDS Plus shanks. Recesses for sockets and switches can be gouged out or drilled out with a crown. If you choose to drill, stock up on an SDS Plus concrete bit larger than the box diameter. Do not forget that there must be room for the mortar in the recess..
- Locksmith chisel (useful if it becomes necessary to cut off the reinforcing wire), hammer, knife.
- Tools with insulated handles up to 1000 V. Screwdrivers, positive and negative, side cutters, pliers.
- Voltage indicator in good condition.
- Measuring tape at least 7.5 m long.
- Soldering iron 60 W.
- Spatula for securing junction boxes and wires with mortar.
- Three-core copper wire. For example, PSVV 3×1.5, the price is 18–20 rubles. per meter, PSVV 3×2.5, price 32–33 rubles. for one meter.
- Junction boxes and sockets (switches). Junction box ABB, price per unit 76-173 rubles. depending on what the screws are made of. Socket box for installation in concrete, price per unit 7-10 rubles.
- Solder for soldering wire connections.
- PVC tape, PVC tube for insulating wire connections.
- Plastic brackets for fastening wires in furrows, expansion dowels (plugs) with screws for installing brackets.
- Fast-setting building mix based on gypsum or building gypsum (alabaster). For example, a universal plaster mix ROTBAND KNAUF, a bag weighing 30 kg at a price of 306 rubles.
- Spring wire with a cross-sectional diameter of 1-1.5 mm for pulling the wire into the channels.
Protective equipment: special glasses, respirator.
Buy all wiring accessories, wire, alabaster. Determine the overall dimensions of the boxes. Prepare your tools. Dilute the plaster mix and determine the start and end times for setting. Practice tinning and soldering wires so that overheating does not melt the protective sheath. Learn to strip conductors without cutting the conductor.
When working with a hammer drill, protect your eyes with glasses from concrete fragments. Lenses in these glasses are made of impact-resistant glass or plastic. For respiratory protection, use a respirator that can be used for single use. If the work is done by two people, reduce dust with a vacuum cleaner. Do not touch the drill immediately after drilling – you will get burned.
Sequence of work
You will need a socket to connect the power tool. On the other hand, the apartment network must be de-energized. Turn off all circuit breakers and mechanical switches in the power line of your apartment. Find the first wire connection near the apartment’s wire entry (on the wall under the floor slab). Check the absence of voltage in the connections. Disconnect all wires leading to the apartment.
All installation work in the apartment network must be carried out only with the voltage disconnected. Provide protection against accidental power-up.
Connect an extension cord with a portable socket to the wires coming from the general board, wrap well with electrical tape. The wires to the electrical outlet for the electric stove in the kitchen can pass through the wall on the staircase, in which case they are not brought into the apartment. An electrician should disconnect these wires directly from the circuit breaker in the switchboard on the landing and securely wrap them with electrical tape (at least three layers of electrical tape). Switch on the circuit breaker to which the temporary socket is connected and the switch in the staircase. All other machines do not need to be turned on. Check for voltage at the portable outlet. Before starting to dismantle the old wiring, make sure that there is no voltage at all sockets and switches.
Open the wire connections at the top of the walls above sockets and switches. Bite off the twists with side cutters. Disconnect the wire from the sockets, pull it out of the channels. During the dismantling of the old wire, it may turn out that the channels are clogged. The places where this happened can be determined by inserting the wire into the channels. Punch impassable areas with a puncher. At the end of the dismantling, there are already channels for laying a new wire, if the connection points remain in the same place. If not, proceed to hollowing out the grooves for laying the wire and recesses for the sockets.
First of all, hollow out the grooves for the sockets. Outline the place where the outlet will be located according to a template made in advance from cardboard. The diameter of the template must be larger than the diameter of the box, additional clearance must be left for the fixing mortar. If you drill with a crown, draw the center of the hole. Drill holes with a concrete drill along the marked line, then punch out the inside with a chisel. Drilling depth – 10 mm more than the box height. This will allow the box to be inserted and provide a headroom when plugging in the outlet..
Draw vertical lines from the indentations to where the wall meets the floor slab. Along this line, use an 8 mm diameter concrete drill to make holes approximately 15 mm deep. Then punch the strobe with a chisel or lance. Try not to break the groove. In this case, the wire will be well fixed in the strobe and will not jump out. The depth of the groove at its entrance into the mounting place for the socket must be increased for the convenience of entering the wire.
Insert the junction boxes into the pre-existing standard locations under the floor slabs. Secure with alabaster. The cover of the mounting product must not protrude above the wall surface. Pull the wire with a wire in the prepared channels, lay it in the grooves, lead it into the junction boxes. In several places in the groove, fix the wire with plaster. Secure the wire with plastic clips near the socket. To do this, it is necessary to drill holes for expansion dowels. Leave a margin along the length of the conductors in the places where the wires are connected. This is due to two reasons. Firstly, the wire should not be taut at the junction to ensure reliable permanent contact. Secondly, it may be necessary to shorten the wire in case of damage. When cutting the wire, leave a margin of at least 200 mm in length.
Connect wires that have the same sheath color. Do not forget that the phase wire must come directly to the switch. The neutral wire must be directly connected to the ceiling lamp, the phase is supplied through the switch. Strip the insulation from the end of each wire to a length of 25-30 wire diameters, strip the copper surface, irradiate, twist tightly, solder with solder. Then put three layers of insulation on the twist, put a PVC tube on top. Store connections and wire stock in the junction box.
Ring the wires from the first junction box to every outlet and every switch. Runs to detect breaks and bad connections. It is best to use a multimeter for this. If you make a mistake at this stage, then you will open the joints. There should be no transition anywhere from the phase conductor to the neutral and to the grounding, from the neutral to the grounding conductor. Such measurements can also show where a loose connection is made. If you find errors in the installation, eliminate them. Close the junction boxes, insulate the wires that fit the outlets.
Boxes for sockets and switches are installed in their original places after leveling the walls, before final processing. If the apartment network is already connected to the general board, turn off the voltage. Check its absence on the veins. Put a supply of wire in the gap between the bottom of the recess and the bottom of the box, put the wire into the box. Apply a layer of reinforcing mortar to the walls of the recess, after wetting these areas with water. Place the box on the work area and align it. Remove excess mortar with a spatula. Sockets and switches are installed in their places after finishing the walls. Until then, all wires must be permanently protected with insulating tape..
Wire laying, connection to the board
The work is performed by an electrician:
- laying the wire from the junction box in the hallway to the staircase;
- connection of wires in the box;
- checking the installation of the apartment electrical network;
- connection of wires in the general board;
- voltage supply, test switching of electrical appliances in the apartment.
The quality of operations must be checked throughout the entire repair. If everything is done correctly, the electrical wiring in the apartment will work reliably.