Since ancient times, there was only natural light in the baths - through a small window. With the advent of affordable electricity, conditions improved markedly. However, wiring in the bath requires a careful approach due to high humidity and temperature. It will be comfortable in the steam room if there are no extra wires and switches in it, and each lamp has its own place.
Air entry into the electricity bath
Wiring in the bath is connected from the home switchboard. The cable is laid underground or pulled through the air, which is much easier. In doing so, the following rules should be observed.
Laying electricity over roads is carried out at least 6 m, and over sections where pedestrians pass - from 3.5 m or more.
Air entry into the building is carried out at a height of at least 2.7 m. For this, insulated wires of the SIP series with a cross section of at least 16 mm are used2. They do not need a carrying cable. Its role is played by a neutral wire, which canbe with or without insulation. Wires are attached to brackets with anchor clamps. They are difficult to insert into the shield due to their high rigidity. Therefore, outside the building, the wires are connected to a copper cable such as VVGng or NUM. It is introduced into the house through a metal pipe inclined to the street by 5-100. The cores of the input cable are connected to the SIP using sealed piercing clamps.
Underground cable entry
Underground input is made by armored cables of the VBBSHV or VBBSHVNG type. For them, soil shrinkage and rodents are not dangerous. The cross section of the cores is from 10 mm2. The cable is placed in a trench 70-100 cm deep, in a layer of sand. To eliminate the appearance of tension during soil shrinkage, laying is done in waves. It is not recommended to use metal pipes to protect the cable, since condensate accumulates in them. It is advisable to use them when the cable is pulled vertically from the ground to a wall or pole.
In the waiting room, a shield is mounted into which the cable is inserted.
Methods of connecting electricity
From home, the connection to the bath is usually made single-phase, but three-phase is also possible. In the first case, the current is supplied to the consumer through the phase wire, and goes back through the zero one. In a three-phase circuit, current flows to the load through 3 wires, and returns one at a time. Some electrical appliances may only be connected in this way.
The advantages of a three-phase network are as follows.
- Power can exceed 30 kW, although this is not required for a bath.
- Electrical appliances can be connected with both single and three-phasefood.
The disadvantage is the need to install special equipment in the shield. In addition, all phases must be evenly loaded for the correct operation of the network.
Wiring requirements
- A separate line from the electrical panel to the bath should be equipped with a circuit breaker. Cables run from it to lighting fixtures such as VVGng and NUM. They can heat up to 70 0C and do not sustain combustion.
- Wiring in the bath for the steam room is selected with a heat resistance of 170-180 0С (Types PMTK, PVKV, RKGM, APPV, etc.). It must not be mounted close to the oven. The heat and moisture resistant silicone insulated cable is brought out into a box located in a place where there is no high humidity and temperature, and then a regular wire is connected to it, which goes to the shield.
- Concealed wiring is installed, but open wiring is also allowed. In brick walls, it is laid under a layer of plaster. It is pulled along wooden surfaces in corrugated pipes attached with metal brackets. Metal pipe protection is not allowed due to corrosion.
- Touching wires to wooden surfaces is not allowed. To do this, all electrical equipment is located on heat-resistant gaskets made of asbestos or ceramics. Insulators are arranged horizontally in increments of 35-40 cm, and vertically - 2 for each log.
- Wires for single-phase input are taken three-core to ensure grounding of devices.
Requirements forelectrical equipment
- The lighting in the steam room is the only electrical appliance that can be used there, but an electric stove can also be installed.
- All equipment is selected with a degree of protection against moisture not lower than IP44 (splashproof version). If LED pool lights that can be submerged in water are used, they have a maximum protection rating of IP68.
- The shield is mounted in a dry room, for example, in a dressing room. It should have a main input, automata and RCDs for 5-10 mA. It is advisable to power the lamps from a step-down transformer.
- EIC rules require the installation of a temperature limiter in the steam room for an electric heating furnace up to 140 0С.
- Luminaires for high temperatures are installed with a moisture and heat resistant shade and a ceramic cartridge. The metal parts of the case are grounded. Any fixtures used in bathrooms are suitable for washing. Lighting voltage is usually 12 V or 24 V. Pool and fountain lights can be used, which can be under jets for as long as necessary or be immersed in water. They work from transformers and have increased electrical safety. Natural lighting is welcome in the steam room.
- Electric floor in the bath is required if the coating is made of ceramic tiles on a concrete base. It is mounted in a screed, in a layer of tile adhesive or on top - in plastic heat-resistant mats. Power is 180-220W/m2. From above, the heaters are covered with a layer of aluminumfoil that is grounded.
- Wire connections in the bath are made on the basis of their minimum passage through the washing and steam room.
- Lights are mounted on walls where the temperature is lower than on the ceiling. The power of incandescent lamps should not exceed 60 W.
How to calculate electrical wiring?
Calculation of any electrical wiring begins with determining the power of all devices. For lighting, you need 1-2 kW. About 3 kW will be needed for a washing machine. An electric stove consumes 5 kW or more.
The wire from the house to the opening machine of the bath shield takes the entire load and its cross section will be maximum (usually - 4 mm2). Then a separate cable will go to the electric furnace. Its cross section will be slightly smaller than the main one, since the maximum power is consumed (2.5 mm2). Separate lines for lighting and sockets with smaller wire sections are also connected. For each of them, its own power consumption and allowable cross section are calculated.
Important! Wiring in the bath should not overload the power supply system in the house. Before installing it, you need to determine how much power the home network will pull.
Power of electrical equipment
Determination of power is not difficult, since it is indicated on the equipment. The first number means voltage (12V, 24V, 220V) and the second number means power in kW. Depending on the magnitude of the total load, the cross section of the cable cores is selected. At a rough estimate, 1 mm2 of the cross section of a copper wire accounts for 10 A of load. More precisely, it can be determined from the tables, which take into account the method of laying. For example, an underground cable will require a larger cross section than an air cable. A 20% power reserve is added to the calculated values. Usually for a bath take a wire with a cross section of 4 mm2.
Choice of machines and RCDs
Circuit breakers are used to protect wiring from short circuits and overloads. The machines are selected according to the operating current 10-15% below the maximum allowable value for the wire. They differ by class. For moderate loads to which house and bath wiring is subject, class C circuit breakers are usually used. A two-pole machine is placed at the input of a single-phase network, and single-pole ones are placed on the lines extending from the shield. It is important that the connection is made through a phase wire.
An important device in the shield, necessary for a room with high humidity, is an RCD. It is selected from the standard row, one step higher in face value than that of the machine connected in front of it. If the latter is rated at 25 A, then the RCD is taken at 30 A.
Internal wiring device
Wires are laid at the bottom of the walls. A sealed socket with a cover or a switch has an entry from below or from the side. With side entry, the wires are bent into an elbow to prevent moisture from dripping inward.
The wires enter the steam room through the wall, at the locations of the lamps. Their free ends should be with a small margin,to conveniently connect to the terminals.
Electrical appliances are grounded if they have metal body parts. For this, the supply cables are selected as three-core.
All wires from electrical appliances are collected in the shield.
Wiring
- Drawing up a wiring diagram in the bathhouse.
- Installing the shield. It is needed to distribute electricity to consumers. Free access is provided to it, the possibility of ventilation and exposure to high temperature and humidity is not allowed. For ease of maintenance, the shield is installed at a height of 1.4-1.8 m. An introductory machine is placed in it, to which a gray phase wire and a blue neutral wire are connected. The yellow-green ground wire is connected to a protective block, from which wiring is made to electrical appliances. The bath requires a separate ground loop. Observing the colors, the wires are bred through automatic lighting lines, sockets and electric furnaces. On the inside of the shield door, a diagram of the entire electrical wiring of the bath is glued. Each machine is signed for which consumer group it is intended.
- Cable wiring from the shield. Laying is done only horizontally and vertically. Bends and twisting are not allowed. Installation is carried out by open, closed or combined methods. The open method involves laying over wooden surfaces, through a corrugated hose, cable channel or tray made of materials that do not support combustion. On wooden surfaces, strips of insulating materials are placed under them, protruding 10 mm from both sides of the pipeor box. In places of attachment, this must be done without fail. On walls or ceilings, wiring is laid on insulators, rollers, cables or strings. Wire connections are made only in junction boxes. Hidden electrical wiring in the bath is laid only inside the structures, in corrugations or closed boxes (in the wall, in the ceiling, under the removable floor, in the ceiling, inside the structures).
- Connecting fixtures. The body is selected metal, and the ceiling - glass. In the washing and steam room, it is allowed to conduct voltage from 12 V to 36 V to the lamps. Wires for lighting are selected with a cross section of 1.5 mm2.
- Connecting outlets. They are installed only in the dressing room or rest room. Wire section - 2.5 mm2.
- Connection of electrical appliances. The heating tank and washing machine are installed in a dry room.
How to choose an electric furnace?
Connecting an electric furnace. The furnace is surrounded by a wooden fence with asbestos insulation on the inside. It is selected by power, depending on the volume of the room and the required heating rate. In addition, when buying, you should choose the appropriate dimensions, as well as types: wall-mounted, floor-mounted, with a steam generator, etc. They cost from 5 thousand rubles. and higher. The cost of electricity for heating is quite large and not all external power networks will be able to provide power of more than 5 kW, for example, for a summer residence. The sauna heater is installed with a direct cable from the automatic switchboard.
Common mistakes when laying electrical wiring in the bath
- Location of wires to the heater and chimney closer than 0.8 m.
- Wiring closer than 0.5 m to batteries or pipes.
- The use of lamps in the steam room and shower room below the degree of protection IP44.
- For wiring at elevated temperatures, a plastic cable channel is used, which quickly deforms from heat.
- Wiring is located on the ceiling of the steam room. It is especially dangerous to lay it over the stove.
Conclusion
Wiring in the bath operates under special operating conditions. Increased temperature and humidity in the premises require compliance with all electrical safety requirements. With proper design, the right choice of cables with electrical equipment and in compliance with all installation rules, the power supply of the bath will work reliably for many years.
