The enterprises of electrical installation organizations manufacture electrical installation products that allow reducing the installation of switches, sockets and lamps to the assembly of finished structures and their fastening to the building elements of buildings.
During the construction of buildings, especially large-panel ones, they usually provide for all openings, niches and embedded parts for installing lighting equipment and laying lighting networks. So, switches and socket outlets with hidden wiring are installed in ready-made niches, boxes or glasses, fastened with screws, screws or spacers on them. Enterprises of NPO Elektromontazh of the USSR Minmontazhspetsstroy serially manufacture embedded boxes (adjustment, branch, ceiling) and other products for electrical wiring in polymer pipes, embedded in reinforced concrete panels during their manufacture at reinforced concrete products factories, from polymer materials.
Skirting board sockets and ceiling switches have metal bases and are attached directly to the wall, usually by shooting. Switches and socket outlets for open wiring, ceiling and wall lamp sockets, as well as ceiling and wall lamps with incandescent lamps (except for those with special bases) are installed on wooden sockets and fastened with screws.
Hanging lamps are attached to the floors on hooks. Factories produce several types of hooks and other fixtures for attaching luminaires to ceilings made of both hollow-core slabs and monolithic structures (Fig. 8). Hooks and studs with swivel bars allow you to lead them into the hole in the ceiling and fix it from below, which greatly facilitates their installation. In accordance with the requirements  for the suspension of fixtures with metal cases in residential and public buildings, the end of the hooks must be covered with insulation.
Rice. 8. Installation of fixtures:
a – hook for hanging the lamp to the ceiling of hollow core slabs; b—stud for fastening the lamp to the ceiling of solid slabs; c – suspension for mounting the lamp on a cable; d – general view of the lamp suspension on a cable.
To close the hole in the ceiling at the point where the wires are connected to the lamp, plastic ceiling sockets are used. The connection of the wires of the network and the lamp in these cases is performed using terminal blocks.
Hanging lamps are attached to walls, columns and trusses using various types of brackets, racks, girths and suspensions. For these purposes, factories produce both complete brackets and individual assemblies and parts that make it possible to complete various kinds of structures (brackets, suspensions, fastening straps) for installing luminaires with fluorescent lamps, DRL and incandescent lamps.
Luminaires in workshops on transitional and special bridges are installed on swivel brackets mounted on racks (Fig. 9). The design of the bracket allows you to raise the bracket by 45° during installation and operation, turn the luminaire towards you and easily change the lamps, and clean the reflector. The wires of the lamp are connected to the network using a plug connector. A system of holes is provided on the rack, which allows you to adjust the height of the luminaires in height, install on the rack the control gear and branch box with a plug connector. With cable wiring, the lamps are suspended from the cable and trusses using pendants (Fig. 8, c and d).
With single-row and double-row suspension of fluorescent lamps on cables, under ceilings and near walls, steel boxes of the KL type are used for laying power wires (Fig. 10).
Two-meter sections of the boxes are connected to each other in a continuous line with the help of nozzles located at one of their ends. The box is attached to the ceiling, wall or cable using brackets, brackets and hangers. Brackets are made of two types – fixed and swivel. The swivel bracket has a swivel head that allows you to fix the box and fixtures at an angle of up to 45°. Luminaires are connected to the network using clamps without cutting the main wires laid in the box.
Rice. 9. Bracket for mounting two fluorescent lamps on the bridge:
a – working position; b – repair position; 1 – rack with mounting tabs; 2 – console with a swivel hook; 3 – hook; 4 – articulated traverse; 5 – junction box with a plug connector; 6 – intermediate position; 7 – position for service.
The continuity of the earthing circuit of the ducts is ensured by welding the strips at the ends of the sections. To supply electricity and install lamps in the workshops of industrial enterprises, complete SCO plug-in lighting busbars are used.
A common disadvantage when installing luminaires located in a line using CL ducts, NL trays and SCO busbars is the need to attach them to supports every 2 m.
Rice. 10. KL box for luminaires with fluorescent lamps and swivel bracket:
a – section of the box for a single-row suspension of fixtures; b – the same, but for a two-row suspension of lamps; c – swivel bracket.
Due to the fact that the lighting lines in most cases are located across construction farms with a step of 6-12 m, it is necessary to install additional supports associated with significant labor costs, up to 40% of all labor costs for the installation of electric lighting. Belelektromontazh Trust has developed and is widely implementing an industrial method of mounting lighting for industrial premises with a linear arrangement of luminaires mounted on mounting blocks assembled outside the installation area in the MEZ. The luminaire unit is mounted on a structure (farm UEMIT-43), which has sufficient rigidity to carry, without additional fasteners, loads from six two-lamp fluorescent luminaires weighing up to 80 kg. Farm weight 27.1 kg. In 1985 8,500 farms were made at the trust’s factories. In the MEZ, lamps and a section of the group network are mounted on trusses. Finished blocks are transported on a special frame to the assembly area, where, before the block is raised to the design mark, lamps are installed and the performance of the lighting device is checked. The block rises to the design mark and is attached to the building structure, the cable stock is connected to the junction box of the neighboring block. Work at height is carried out in one stage and makes up no more than 20% of the laboriousness of the installation of a lighting installation. The consumption of metal compared to traditional methods is reduced by at least 50%.
When installing lighting equipment, the following basic requirements are met: fixtures in a row and in height are aligned so that their deviations are not noticeable to the eye; installation products are fixed in the center of sockets, niches, the position of their handles, buttons and sockets is strictly aligned vertically and horizontally; switches on the walls are installed at a height of 1.5 m from the floor (to the axis); socket outlets are installed at a height of 0.8-1 m or 0.3 m from the floor; in schools and kindergartens, nurseries, in rooms for children, plug sockets are installed at a height of 1.5 m.
Switches and circuit breakers with lever and key handles are installed so that when the circuit (lighting) is turned on, the handle moves up (pressing the upper part of the key). Plug sockets are installed so that the sockets are located horizontally. General lighting switches, as well as sockets installed at the entrance to the room, as a rule, are placed so that they are not obstructed by the opening door. Switches for bathrooms and sockets are installed outside these rooms.
Installation products, luminaires, their diffusers and protective nets must be firmly fixed. Hooks and other fixtures for hanging lamps weighing up to 100 kg are tested for 10 minutes by five times the mass, and lamps (chandeliers) weighing more than 100 kg are tested by twice the mass plus 80 kg. When fixing luminaires to the ceiling on dowels driven in with a mounting gun, each suspension point is tested with triple the mass of the luminaire plus 80 kg. Lamps for general lighting, unless otherwise specified in the project, are installed with the direction of the luminous flux vertically downwards. Lamps of local and local lighting, in accordance with their purpose, are fixed motionlessly so that they stably maintain the position given to them.
Each floodlight must be carefully focused according to the shape of the light spot on a vertical surface, and in its absence – on a horizontal surface with the greatest possible inclination of the floodlight housing. After that, the floodlights are turned and tilted in accordance with the instructions given in the project, with an error of no more than 2 °, and firmly fixed in this position.
Glasses and diffusers of lamps are thoroughly wiped or washed before installation. Luminaires are supplied for installation charged with wires. At the point of entry into the luminaire, the wires should not be subjected to mechanical damage, and the contacts of the cartridges should be unloaded from mechanical stress . Luminaires on cranes and devices subject to shock or vibration are suspended using spring devices.
When installing the shields, the distances from non-insulated, live parts to grounded metal non-current-carrying parts are kept at least 15 mm along the insulation surface and 10 mm in air. Shields and points are provided with inscriptions indicating the number of the shield, as well as the purpose or number of each line in accordance with the diagram and plan of the electrical network.