Repair of lamp equipment and their elements. Maintenance of lighting electrical installations. Maintenance of lighting electrical installations
Photometric measurements of illumination in the main production and technological workshops and premises with monitoring of lamp power compliance with the design and calculations are carried out once a year. Illumination is checked using a lux meter in all production workshops and at main workplaces. The obtained illumination values must correspond to the calculated and design ones. Before you begin checking the illumination, it is necessary to establish the places where it is advisable to measure the illumination. The results of inspections and checks are documented in acts approved by the chief power engineer of the enterprise. Peculiarities of operation of gas-discharge light sources Peculiarities of operation of fluorescent lamps and high-pressure gas-discharge lamps The industry produces the following gas-discharge light sources with lamps: low-pressure fluorescent mercury; high-pressure mercury arc (DRL type); xenon (DKsT type) high pressure air-cooled and ultra-high pressure water-cooled; high and low pressure sodium lamps. The first two types of lamps are most widespread. Gas discharge lamps have the following main features. The luminous efficiency (efficiency) of incandescent lamps is in the range of 1.6-3%, and their luminous efficiency does not exceed 20 lm/W of power consumption for high-power lamps and is reduced to 7 lm/W for lamps with a power of up to 60 W. The luminous efficiency of fluorescent lamps and DRL lamps reaches 7%, and the luminous efficiency exceeds 40 lm/W. However, such lamps are connected to the electrical network only through ballasts (ballasts). It takes some time to light a fluorescent lamp and especially a DRL lamp (from 5 s to 3 - 10 min). The main element of the ballast is usually an inductive reactor (reactor), which worsens the power factor; Therefore, capacitors are used that are built into modern ballasts. The industry produces general-purpose fluorescent lamps with power from 4 to 200 W. Lamps with a power from 15 to 80 W are mass-produced in accordance with GOST standards. The remaining lamps are manufactured in small batches according to the appropriate technical specifications. One of the features of using fluorescent lighting is that it is more difficult to find a fault compared to using incandescent lamps. This is explained by the fact that the most common circuit for switching on fluorescent lamps contains a starter and a choke (ballast resistance) and becomes much more complex than the switching circuit for an incandescent lamp. Another feature of fluorescent lighting is that for normal ignition and operation of a fluorescent lamp, the network voltage should not be less than 95% of the nominal one. Therefore, when operating fluorescent lamps, it is necessary to control the network voltage. Normal operation of a fluorescent lamp is ensured at a temperature of 18-25 °C; at a lower temperature, the fluorescent lamp may not light up. During operation, fluorescent lamps are inspected more often than incandescent lamps. It is recommended to inspect fluorescent lamps daily, and clean them from dust and check their serviceability at least once a month. During operation, it is also necessary to take into account that after the end of the normal service life of a fluorescent lamp (about 5 thousand hours), it practically loses its quality and must be replaced. A lamp that only blinks or glows at one end must be replaced. Proper organization of the operation of the lighting installation and conscientious daily care of it ensure that it remains operational and complies with current rules and regulations. When developing a lighting installation project, it is necessary to resolve issues related to the maintenance of lamps and access to elements of the electrical network.
When the height of the lamp suspension is more than 4.5 m(maximum height for servicing from a stepladder) a number of methods can be used to access the elements of the lighting installation. For example, service from overhead installation, repair and technological cranes or crane beams equipped with special fenced platforms.
If there are a significant number of lamps and their placement in rows, it is advisable to install special lighting bridges, which are located above the cranes and allow work on servicing electrical equipment to be carried out regardless of the operating mode of the cranes and at any time of the day.
When placing lamps in groups and for servicing single lamps, provision may be made for the installation of fenced lighting platforms or the installation of special brackets with back arches.
Power supply diagram for the lighting installation from two diode transformer substations: 1 - transformer substation, 2 - power load, 3 - working lighting, 4 - emergency lighting.
If there is a technical floor, it is possible to organize servicing of lamps from it, and in some cases it is possible to lower the lamps down to service them from the floor. Maintenance of lamps using mobile telescopic towers and retractable ladders of various designs is also widely used.
However. No matter how well a lighting installation is designed and installed, it can quickly become unusable if there is no regular maintenance and its operation is carried out at a low technical level.
Regardless of the type of light sources used, for any lighting installation there are general requirements for operating personnel and for the organization of operation. These requirements can be formulated as follows.
The basic rule of operation comes down to regular monitoring, timely repairs and elimination of detected problems in the operation of all elements of the lighting installation. Since in most cases it is possible to detect malfunctions of individual elements of the installation only by the lighting mode of the lamps, it is necessary to systematically keep an operation log in which it is necessary to note data on the operating mode of the lighting installation (burning time of lamps, changing lamps, cleaning time of lamps, data on network insulation measurements , replacement of failed lamp elements and their repair, etc.).
The operation of the lamps is strongly influenced by the voltage in the supply network and its deviation from the nominal value, therefore it is necessary to monitor the maintenance of a constant voltage in the network, identify and eliminate the causes of sudden voltage fluctuations. The actual service life of the lamps very often depends on precise control of the supply voltage conditions.
During the operation of a lighting installation, a decrease in the initial level of illumination at workplaces occurs, due to a gradual decrease in the luminous flux of lamps due to their aging, as well as as a result of contamination of lamps, walls and ceilings of the room.
Dust and soot, settling on the reflective surfaces of lamps, covering the diffusers and lamp bulbs with a thin layer, cause additional absorption of the luminous flux created by the light source, and thereby reduce the efficiency of the lamp. Gradual contamination of walls and ceilings reduces their reflectance, while their absorption of light flux increases, which also leads to a decrease in illumination of workplaces.
In this regard, the good condition of the lighting installation is determined by timely and thorough cleaning of lighting electrical equipment elements from all types of contaminants, regular painting of walls and ceilings of premises and carrying out routine preventive inspections and routine repairs of electrical equipment.
Along with the listed factors, operating personnel should pay attention to the inadmissibility of installing lamps of lower power than those provided for in the design when replacing burnt-out lamps. It is also prohibited to use lamps without luminaires, or to remove diffusers and shielding grilles from luminaires, as this leads to a deterioration in the quality of the lighting installation due to an increase in the glare of the lighting fixtures.
Operational personnel are responsible for timely cleaning of natural light openings and carrying out measures to save energy consumption for lighting purposes. Very often there are cases of misunderstanding of the last requirement, as a result of which some of the lamps are turned off or the power of the lamps installed in them is reduced to save money. Such actions lead to deterioration of lighting conditions, lead to a decrease in labor productivity, and an increase in injuries and are therefore unacceptable.
Checking light levels in workplaces can be done using a light measuring device called a lux meter. The most convenient is a portable lux meter of the Yu-16 type. This device consists of a light detector, a selenium photocell, and a galvanometer with a pointer. The scale of the device is graduated in units of illumination - lux. When measuring illumination, it is necessary to monitor the voltage of the supply network.
If the voltage deviates from the nominal voltage by more than ±5%, measurements cannot be made, as this leads to large errors. It should also be kept in mind that the lux meter is calibrated to measure illumination from incandescent lamps. When measuring illumination from fluorescent lamps of the LD type, it is necessary to enter a correction factor of 0.9, and in the case of lamps of the LB type, a correction factor of 1.1.
Light measurements must be taken at least once a month at certain points located in different areas of the workshop. Pre and In general, measurements are made in those areas where precise work is performed that involves high visual strain. The results of illumination measurements are recorded in the operating log of the lighting installation.
When developing a lighting project, a safety factor is usually introduced into the calculations, taking into account the decrease in illumination during operation of the installation (aging of lamps, contamination of lamps and room surfaces, etc.). This coefficient is different for fluorescent lamps, and also depends on the nature of the room environment (for incandescent lamps it is taken from 1.3 to 1.7, for fluorescent lamps from 1.5 to 2.0).
When monitoring illumination at the beginning of operation of an installation or during its operation after replacing lamps with new ones and cleaning fixtures, the results of illumination measurements should be 1.3-2.0 times higher than the normalized value (depending on the accepted safety factor for a given installation).
To organize the correct operation of the lighting installation, operating personnel must have the necessary technical documentation of the installation. After completion of installation and commissioning work, the installation organization hands over the completed lighting installation to the operating personnel. At the same time, as-built drawings are drawn up that reflect the actual implementation of the lighting installation. These drawings must contain data on the main and group network of each room, types of installed lamps and lamp power, illumination of individual rooms, data on types of group and distribution boards, currents of fuse links and rated currents of circuit breakers, etc.
When transferring the installation into operation, protocols must be drawn up to measure the insulation resistance of cables and wires, acts for hidden work, measurements of the actual illumination of rooms and individual workplaces, etc.
During the operation of the lighting installation, with all changes made to the existing installation, appropriate adjustments must be made in the as-built drawings. It is necessary to strictly ensure that the technical documentation is maintained in exemplary order at all times and reflects the actual state of the installation.
The correct rational form of organizing the operation of the lighting installation is of great importance. Several such basic forms may be recommended, the choice of which should be decided specifically at each enterprise, depending on local conditions.
The most common form of operating a lighting installation is servicing the lamps at the installation site by operating personnel. With this form of operation, calculations show that for every 50-120 kW installed power of light sources, it is necessary to have one fitter of the 3rd category. The lower power limit applies to installations with gas-discharge lamps, and the upper limit to installations with incandescent lamps when servicing lamps from stepladders or ladders.
At large enterprises, it is rational to organize specialized teams to service lighting installations with the creation of lighting workshops at large workshops. Such workshops can be created separately or as part of electrical repair shops. The workshop should have a stock of cleaned and tested lamps.
Lamps that require cleaning and maintenance, as well as those that are out of order, are removed by staff from the installation site and sent to the workshop, and in their place others are immediately installed from the available stock. With such a maintenance system, significant cost savings can be obtained, since instead of processing each lamp manually at the installation site, it is possible in the workshop to have specialized productive equipment for cleaning lamps, stands for testing them, etc. All this reduces the unit cost of servicing each lamp .
Diagram of the lighting system of the projection installation: 1 - elliptical reflector, 2 - UV radiation source, 3 - protective glass, 4 - fly-eye honeycomb condenser, 5 - selectively reflecting mirror, 6 - bandpass filter, 7 - condenser lens.
It is also possible to organize specialized lighting workshops to service a number of enterprises. In such workshops, high industrialization of lamp processing can be achieved and thus the cost of this work can be reduced. Lighting workshops can serve enterprises on a contractual basis, and in some cases such a system for organizing operation may turn out to be more economically profitable compared, for example, with a system for cleaning lamps at the site of their installation.
With the growing volume of lighting installations, when several thousand lamps are installed in workshops and when the use of gas-discharge light sources begins to become increasingly important, the cost of operating lighting installations becomes extremely important. One of the main items of these expenses is the cost of replacing burnt out lamps. With a large number of installed lamps, the problem of replacing them arises.
There are three ways to replace lamps: individual, group and combined. In the first case, each burnt-out lamp is replaced with a new one. With group replacement, it is assumed that all lamps used in one room or part of it are installed at the same time and, after burning for a certain time, are replaced with new ones. The third method is a combination of the first and second.
It is known that incandescent lamps have an average lifespan of 1,000 h, and, according to the standard, the luminous flux of each lamp after 750 h combustion should be at least 85% of its original value. Since the luminous flux of incandescent lamps decreases by a small amount during the combustion process, there is no point in stopping the use of the lamps before they burn out.
If we take into account the safety factors adopted when designing lighting installations, a possible decrease in the luminous flux of incandescent lamps due to their aging when 15-20% of all lamps installed in a given room burn out, they need to be replaced with new ones. Thus, in installations with incandescent lamps, it is possible to use a combined method of replacing lamps.
A completely different picture emerges in installations with fluorescent lamps. According to the standard for these lamps, their average service life should be 5,000 h, and the luminous flux after this burning time can be on the order of 60% of its average nominal value. Some lamps fail before they burn out up to 5,000 hours, while another part of the lamps can burn for a longer time, but at the same time significantly loses luminous flux. With a greater loss of luminous flux, further operation of such lamps becomes economically unprofitable. Therefore, it is necessary to distinguish between the effective service life of the lamp, when its use is still economically profitable, and the full service life before it burns out.
The effective lamp life will be less than the actual lamp life possible. If you operate an installation with fluorescent lamps and replace the lamps only after they fail, this can lead to a sharp decrease in illumination below the standard level, which is unacceptable. Therefore, replacement of lamps should be carried out after the effective service life of the lamps has expired, although in practice they may still burn. It should be emphasized that for installations with fluorescent and other gas-discharge lamps, the indicators of the need to replace the lamps are not their burnout, but their effective service life.
Thus, if in the case of incandescent lamps with a system of individual or combined replacement of lamps, the need to replace them is determined by the fact that the lamps burn out, then in installations with gas-discharge lamps this problem is more difficult to solve. In this case, it is possible to keep an individual record of the burning time of each lamp, but in practice this is difficult to do. In this regard, the idea of group replacement of lamps arose, when all lamps installed in a room or part of it are simultaneously replaced.
The advantages of this method of replacing lamps can be considered a sharp reduction in the cost of maintaining the installation and a reduction in the time required for its implementation, an increase in the average level of illumination in the workplace and a reduction in unproductive energy consumption due to a decrease in the efficiency of lamps as they age. Lamp replacement can be done at any time of the day, without interfering with the technological operating mode of the enterprise, and it can be combined with the time of cleaning the lamps.
The disadvantage of this method of replacing lamps is the greater consumption of lamps. However, after removing the lamps, they should be checked for the amount of luminous flux, and those lamps that still have a sufficiently large luminous flux can be placed for further use in auxiliary rooms. This slightly reduces the increased consumption of lamps.
The profitability of using a group method of replacing lamps in each specific case is determined by an economic calculation, which takes into account the accepted safety factors, the cost of individual and group replacement of lamps, the dependence of the reduction in the luminous flux of lamps on the burning time and a number of other factors. The effective service life of lamps is also determined on the basis of technical and economic calculations, and for domestic fluorescent lamps it lies in the range of 3,500-5,000 h.
1.0General information about electrical installations……………………………2
1.1 Types of lighting………………………………………………………...3
1.2 Lamps and spotlights…………………………….. ………...4
2.0 Connection diagrams for electrical light sources……………..8
2.1 Switching circuits for incandescent lamps……………………………8
2.2 Switching circuits for fluorescent lamps………………………...11
2.3 Schemes for switching on DRL lamps……………………………...................13
3.0 Operation of lighting installations…………………………..15
3.1 Replacing lamps and cleaning fixtures……………………………..16
3.2 Devices for servicing lamps………………..18
4.0Routine preventive inspection, testing and repair of lamps………………………………………………………………………………….21
5.0Safety precautions when working in electrical installations with voltages up to 1000 volts……………………………………………………………24
5.1 General information……………………………………………………...25
5.2 Rules for working with electrified tools………...27
5.3 Work in electrical installations with voltages up to 1000 volts.................................28
6.0 References……………………………………………………………......29
1.0 General information about electrical installations.
The design, execution and normal operation of electrical installations in which electricity is produced, converted, distributed and consumed depend on the environment. Different requirements apply to electrical installations, external (open) and internal (closed). The rooms in which electrical installations are installed, depending on the state of the environment (temperature, humidity, dust, gas contamination) are divided into dry, damp, damp, especially damp, dusty, with a chemically active environment, hot, fire and explosive. In addition, there are premises with increased danger, especially dangerous and without increased danger.
1.1 Types of lighting.
Electric lighting installations of various types are carried out in all industrial and domestic premises, in public, residential and other buildings, on streets, squares, roads, and driveways. In addition to installations for general use, there are special ones, for example, for irradiating plants in agriculture, for medicinal purposes in medical institutions, regulating and controlling traffic in transport and technological processes in production, etc.
Special electric lighting devices are called lighting installations. The lighting electrical installation includes light sources, lighting fixtures, ballasts, electrical wiring, electrical installation products and devices, panels, shields and distribution devices. In accordance with the rules for the construction of electrical installations (PUE), a distinction is made between general, local, emergency and security lighting.
General - called lighting of all or part of the room;
local – lighting of workplaces, objects, surfaces;
combined – a combination of general lighting with local lighting, creating increased illumination directly at the workplace.
General lighting can be uniform and localized when lamps are placed so that increased illumination is created at the main workplaces.
The main type of lighting to ensure normal activity in all rooms and open areas where work is carried out in the dark or traffic and people move is working.
If it is violated, emergency lighting is used to temporarily continue work or evacuate people. Security lighting is an integral part of the working lighting and is installed along the boundaries of the protected area. Working lighting includes repair (portable) and light-enclosing for chimneys and other particularly tall structures.
1.2 Lamps and spotlights
The luminous flux of most light sources is distributed fairly evenly in space.
For rational lighting of a room or open space, it is usually necessary to distribute the luminous flux of the light source in a very specific way: direct it down or up. For such redistribution of the light flux, lighting devices are used.
Lamps are short-range lighting devices used to illuminate objects located at a short distance.
A spotlight, unlike lamps, is a long-range lighting device and is used to illuminate distant objects.
The lamp consists of a light source and lighting fixtures. The main purpose of lighting fixtures is to redistribute the luminous flux of the light source. It also protects the vision of workers due to excessive brightness of light sources, protects the lamp from mechanical damage, protects the cavities of the location of the light source and cartridge or environmental influences, and serves for fastening the light source, wires, and ballasts.
Optical systems of lighting devices are designed to redistribute the light fluxes of light sources. The elements of optical systems are: reflectors, refractors, diffusers, protective glasses, shielding grilles and rings.
Reflectors – redistribute the luminous flux of the lamp. Depending on the reflection, reflectors can be diffuse, matte or specular.
Diffusers – redistribute the luminous flux of the lamp based on diffuse transmission. There are diffuse, matte and frosted diffusers. The last two have directionally scattered transmission; Matted ones have less scattering power than matte ones.
Refractor – redistributes the luminous flux of the light source reflected from the reflector, redistributed using a diffuser or refractor. Certain types of lamps may not have a reflector or diffuser.
Modern electric light sources are incandescent, low-pressure fluorescent and high-pressure mercury lamps.
Incandescent lamps (Fig. 1), the most common electric light source, have a tungsten filament, most often a spiral one, located in a vacuum or inert gas.
Fig 1. Incandescent lamp.
The principle of operation of incandescent lamps is based on the conversion of electrical energy supplied to its filament into the energy of visible radiation, affecting the human visual organs and creating a feeling of light close to white.
Incandescent lamps, from the internal volume (bulb) of which air has been pumped out, are called vacuum, and those filled with inert gases are called gas-filled.
Gas-filled lamps, all other things being equal, have a greater luminous output than vacuum lamps, since the gas in the bulb under pressure prevents the evaporation of the tungsten filament, which makes it possible to increase its operating temperature, and therefore the luminous efficiency.
Their disadvantage is some additional heat loss from the filament through convection of the gas filling the internal cavity of the bulb. And the main disadvantage of incandescent lamps is their low luminous efficiency: only 2-4% of the consumed or electrical energy is converted into the energy of visible radiation perceived by the human eye, the rest of the energy is converted into heat emitted by the lamp.
To illuminate enterprises, institutions and educational institutions, currently mainly low-pressure fluorescent lamps are used (Fig. 2), which are a hermetically sealed glass tube, the inner surface of which is coated with a thin layer of phosphor.
Fig.2 Low pressure fluorescent lamp.
Low-pressure fluorescent lamps are manufactured for a voltage of 127V with a power of 15 and 20W, for a voltage of 220V - with a power of 30, 40, 65 and 80W. The lamp life under normal operation is 10,000 hours. The light output of fluorescent lamps is approximately 4-5 times higher than that of incandescent lamps.
One of the types of fluorescent lamps are mercury arc lamps(DRL) high pressure, (Fig. 3) which are used to illuminate city streets, squares, as well as the territory and production premises of enterprises and are available in two-electrode and four-electrode types.
Fig.3 High-pressure mercury arc lamp (HALV).
Two-electrode DRL lamps are produced with a power of 80, 125,250,400,700 and 1000 W.
2.0 Schemes for connecting electrical light sources.
There are many schemes for connecting electric light sources. The simplest are the circuits for switching on incandescent lamps, and the more complex ones are fluorescent lamps and high-pressure mercury arc lamps (HALVs).
2.1 Schemes for switching on incandescent lamps.
The connection from the network of two incandescent lamps controlled by one single-pole switch is shown in Fig. 4a. The number of lamps can be more than two.
The five lamps are controlled by two side-by-side single-pole switches (Fig. 4b).
When you turn the switch for the first time, one of the three lamps turns off, with the second, the other two turn off, but the first lamp turns off, with the third turn of the switch all the lamps turn on, and with the fourth, all the lamps of the chandelier turn off.
If it is necessary to independently control one or more lamps from two places, use a circuit (Fig. 4d) where 2 switches are used, connected by two jumpers.
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Jumpers and wires running from the switch to the lamps create the necessary circuits for independent control of the lamps from two places. This scheme is used to illuminate corridors and staircases of residential buildings and enterprises, as well as tunnels with two or more entrances.
Lamps of lighting electrical installations powered from a three-wire, three-phase current system are switched on to the phase-to-phase network voltage (Figure 4d),
and those powered from a four-wire network - between the phase and neutral wires (Fig. 4e.)
2.2 Schemes for switching on fluorescent lamps.
Fluorescent lamps can be connected to the electrical network using starter or starterless ignition circuits.
When turning on lamps with a starter ignition circuit (Fig. 5), a gas-discharge neon lamp with two (moving and fixed) electrodes is used as a starter.
The fluorescent lamp is connected to the electrical network only in series with a ballast resistor, which limits the increase in current in the lamp and thus protects it from destruction. In alternating current networks, a capacitor or a coil with a large inductive resistance - a choke - is used as a ballast resistor.
The fluorescent lamp is ignited as follows. When the lamp is turned on, a glow discharge occurs between the electrodes, the heat of which heats the movable bimetallic electrode. When heated to a certain temperature, the movable electrode of the starter, bending, closes with the stationary one, forming an electrical circuit through which the current necessary to preheat the lamp electrodes flows. When heated, the electrodes begin to emit electrons. During the flow of current in the circuit of the lamp electrodes, the discharge in the starter stops, as a result the movable electrode of the starter cools down and, unbending, returns to its original position, breaking the electrical circuit of the lamp. When there is a break, EMF is added to the network voltage. The self-induction of the choke and the increased voltage pulse generated in the choke causes an arc discharge in the lamp and its ignition. With the occurrence of an arc discharge, the voltage on the lamp electrodes and the starter electrodes connected in parallel with them decreases so much that it turns out to be insufficient for the occurrence of a glow discharge between the starter electrodes. If the lamp does not ignite, then full mains voltage will appear on the starter electrodes and the whole process will repeat.
2.3 Schemes for switching on DRL lamps.
Lamps DRL included in the AC electrical network voltage 220V . Through an ignition device, with the help of which the lamp is ignited with a high voltage pulse (Fig. 6)
The ignition device consists of a spark gap R , selenium rectifier (diode) NE , charging resistor R and capacitors C1 And C2 . The main inductor winding in the circuit serves to prevent a sharp increase in current in the lamp, as well as to stabilize its combustion mode.
Lighting the lamps works like this. When the lamp is turned on, current passes through the rectifier NE and charging resistor R , charges the capacitor C2 . When the voltage across the capacitor C2 will reach approximately 220V , breakdown of the air gap of the arrester occurs R and capacitor C2 is discharged onto the additional winding of the inductor, as a result of which an increased voltage is created in the main winding of the inductor, the pulse of which lights up the lamp L . A capacitor is used to protect the rectifier from a high voltage pulse C1 , Capacitor C3 necessary to eliminate interference to the radio receiver created by the igniter when lighting the lamp.
3.0 Operation of lighting installations.
No lighting installation, as can be seen from numerous surveys, can remain effective unless it is regularly and well maintained. Aging of lamps and the associated decrease in their luminous flux, the accumulation of dust and dirt on the reflective and diffusing surfaces of lamps and lamps, as well as the gradual deterioration of the reflective properties of the surfaces of premises and equipment - all this contributes to the loss of luminous flux and a gradual decrease in the level of illumination.
Aging of light sources is inevitable, but the degree of contamination of lamps and surfaces of premises and equipment can be controlled, and with well-organized operation, the consequences of contamination can be minimized.
Proper organization of the operation of lighting installations should include: careful acceptance of lighting installations after completion of installation work and after major repairs, timely replacement of lamps and cleaning of lamps, scheduled preventive inspection and repair of lamps and the electrical network.
3.1 Replacing lamps and cleaning fixtures.
The preservation of the lighting conditions created by a lighting installation during operation depends on its care and, to a large extent, on the timely replacement of light sources and keeping lighting fixtures clean.
The simplest and, unfortunately, most commonly used replacement method is the individual lamp replacement method, where the lamps are replaced as they burn out. The disadvantage of this is the long-term use of lamps that have lost their efficiency and the associated decrease in illumination created by the lighting installation.
A very important, necessary and labor-intensive part of the operation of lighting installations is the periodic cleaning of lamp bulbs and reflective, scattering and other surfaces and parts of lamps from dust and dirt accumulating on them.
The frequency of cleaning lamps depends on many factors, primarily on the environment of the illuminated room. Thus, lamps in the workshops of a metallurgical plant require more frequent maintenance than those installed in the corridor of a hospital. Similarly, the lamps in the grinding shop should be cleaned more often than the lamps in the meeting room located in the same building.
The number of cleanings determined by Chapter II-A, 9-71 SNiP “Artificial lighting. Design standards" for the amount of dust, smoke and soot contained in the air environment of indoor and outdoor spaces are indicated in Table 1
Number of lamp cleanings.
| Illuminated objects |
Number of cleanings no less |
| Industrial premises where the air contains dust, smoke and soot in quantities: |
|
| 10 mg/m3 or more |
2 times a month |
| From 5 to 10 mg/m3 |
1 time per month |
| No more than 5 mg/m3 |
1 time every 3 months |
| Auxiliary premises with a normal air environment and premises of public and residential buildings |
1 time every 3 months |
| Sites of industrial enterprises where the air environment contains dust, smoke and soot in quantities: |
|
| More than 5 mg/m3 |
1 time every 3 months |
| Up to 0.5 mg/m3 |
Once every 6 months |
| Streets, squares, roads, areas of public buildings, residential areas and exhibitions, parks, boulevards |
Once every 6 months |
3.2 Devices for servicing lamps.
Particular difficulties for the operation of lighting installations are caused by the maintenance of lamps, as a rule, installed at a significant height from the floor (ground). The implementation of work to replace light sources and contaminated parts involved in the formation of the lighting circuit of lamps depends on the availability of devices or devices for accessing them. For this purpose, depending on the installation height of the luminaires, the following can be used: ladders or stepladders, mobile and self-propelled telescopic and articulated telescopic towers, descent devices, suspended and overhead cranes, stationary lighting bridges, vehicles with a basket or platform on a sliding telescopic or articulated telescopic tower.
Ladders and stepladders. According to the “Rules for the Technical Operation of Consumer Electrical Installations”, servicing of lighting installations from these devices is allowed when the height of the suspension of the lamps does not exceed 5 m, by at least two persons. The length of ladders and stepladders must be such that a worker can work standing on a step 1 m from the top edge of the ladder or stepladder. If the stepladder has a platform, it must be fenced to a height of 1 m (Fig. 7)
Fig.7 Stepladder .
Mobile, telescopic and articulated telescopic lifts.
Telescopic lifts are widely and successfully used for servicing outdoor lighting fixtures installed on supports or brackets on the walls of buildings at a height of 6 m or more from ground level.
The use of mobile telescopic lifts, such as those shown in Fig. 8 and Fig. 9, for servicing lamps in industrial buildings is ineffective. These lifts provide a narrow scope of work, limited by the size of the cradle. A large amount of time is spent raising and lowering the telescope before manually moving the lift from one working position to another. As with the use of ladders and stepladders, fixtures should be located so that process equipment and protruding parts of the foundations do not interfere with the installation of the lift. The disadvantages of this type of lifts are the reason for their very limited use in industry.
4.0 Scheduled preventive inspection, testing and repair of lamps.
To ensure the normal operation of the lighting installation, it requires constant supervision. During operation, it is necessary to carry out preventive periodic inspections, checks and repairs of lighting equipment elements. The timing of inspections and repairs is established by the electrical service of the enterprise in accordance with the rules of technical operation, depending on the environment of the room, the features and purpose of the lighting equipment elements.
Lamps, group and main panels, wires, switches, switches, plug sockets are subject to inspection, repair and testing. Recommended timing of scheduled preventive inspections and repairs of all listed elements of the lighting installation are indicated in table. 2.
Inspection and testing of luminaires must establish: the presence, integrity and reliability of fastening of lenses, protective glasses, shielding grilles, reflectors, reliability of electrical contacts, the state of insulation of charging wires, faults that arise in luminaires with fluorescent lamps, which may be caused by lamps, must be installed and eliminated. starters, ballasts, errors in the circuit, etc.
In installations with a large number of fluorescent lamps, it is advisable to check them to detect the causes of damage on a stand in the repair department of the workshop.
At the stand, lamps and luminaire parts removed from service and new ones must be checked before installation. The diagram of such a stand is shown in Fig. 10.
Work on inspection, testing and repair of lamps should be timed to coincide with their cleaning. Parts and parts of lamps found to be faulty or unusable must be replaced during repairs with similar new ones. This, of course, only applies to fairly easily removable parts of luminaires, such as sockets, lenses, protective glass, shielding grilles, starters, ballasts, sealing gaskets, etc. If a part of a luminaire that has become unusable cannot be replaced, the entire luminaire is replaced.
The work on repairing lamps should also include work on restoring the reliability of contact connections and replacing the charging wires of lamps with incandescent lamps and DRLs.
5.0 Safety precautions when working in electrical installations with voltages up to 1000 volts.
Occupational safety measures at various production sites have their own characteristics and are provided for by special instructions. There is a risk of electric shock when using hand-held power tools or using portable lights. The main causes of electrical injuries include temporary electrical wiring, work performed in violation of labor safety rules, work performed without protective equipment and poor-quality grounding of power tools. The main condition for safe work is strict compliance with labor safety rules with the mandatory use of personal protection against electric shock. The applied step-down transformers, welding equipment and production mechanisms operated by electric current are grounded. The voltage of portable power tools should be no higher than 220 volts in rooms without increased danger, and in rooms with increased danger and in the open air - 36 (42) volts, portable lamps must be connected to networks with a voltage of 36 (42) volts. For electric soldering irons, a voltage of 12 volts should be used.
Plugs and sockets for voltages of 12 and 36(42) volts differ in design from household plugs and sockets.
The ground pin of the plug is slightly longer than the working pins. When using power tools with a voltage of 36(42) volts, dielectric gloves, galoshes and mats or paths made of rubber are required. All persons using portable power tools are prohibited from transferring them to others, disassembling or repairing both the tool and the wires.
5.1 General information.
When carrying out repair work in workshops and directly at installation sites, many mechanisms, tools and devices are used, both for general construction use and specialized electrical installation ones. In the workshops, production production lines are created for industrial processing and procurement of pipes, sheet and grade steel, tires, electrical wiring kits, cables, etc. To carry out repair work (installation, dismantling of lamps) specialized vehicles or trailers and mobile workshops are equipped directly at the facilities. All machines, mechanisms and means of mechanization used in electrical installation production can be divided into five groups: mechanized and manual tools, devices and other means of small-scale mechanization (electrified, pneumatic and pyrotechnic tools, plumbing and cutting tools, inverter installation devices); welding equipment (welding transformers, equipment for gas welding and cutting); specialized vehicles and mobile workshops; metalworking machines and mechanisms, concentrated mainly in workshops and repair shops; installation mechanisms for loading and unloading and repair work (automotive cranes, hydraulic lifts and telescopic towers, hoists and winches, blocks and pulleys), as well as general construction mechanisms (tractors, bulldozers, etc.). All of the equipment listed is used to repair lighting at height, or dismantle it if the lamp cannot be repaired on site. When repairing lamps l. lighting workers use tools to connect and terminate wires and cables. KSI-1 pliers are designed for removing insulation from the ends of wires with a cross-section of 0.75 - 4 mm 2 and cutting them and consist of three parts, hingedly connected to each other: a lever for clamping the wire, a lever with knives for cutting the insulation and a lever with a slider - eccentric , moving the clamp and shaped knife in the jaws of the pliers.
KU pliers (universal pliers), which resemble pliers in appearance, are universal; they can perform six installation operations: cutting wires, stripping wires, cutting jumpers, removing insulation, making rings and clamping wires.
Electric drilling machines. Depending on the drilling diameter, electric drilling machines come in three versions: pistol type for drilling small diameter holes (up to 8 - 10 mm); with one top closed handle – for holes with a diameter of up to 15 mm; with two side handles and a chest or screw stop - for holes with a diameter of more than 15 mm.
Inventory stairs. The ladder with a platform is used for work at a height of up to 4.5 m. The support posts are welded from aluminum sheet, the platform measures 500 x 600 mm with a fence. Load capacity 1 kN weight – 32 kg.
The folding ladder, welded from aluminum sheet, consists of two links and can be used as an extension ladder or as a stepladder. The size up to the top step in working position as an extension ladder is 3280 mm, and as a stepladder 2120 mm. Load capacity in both positions is up to 1 kN, weight – 11.5 kg.
Repairs are divided into complex and minor. Minor repairs include replacing the glass bulb, starter, choke, or insulating the wire inside the lamp body at a low height (3 meters). Lamp repairs are carried out using a stepladder or a folding ladder. The work is done by two people. One worker is working, the other worker is insuring (giving tools).
Complex repairs are when work is carried out at high altitudes (in high-rise workshops, on lighting poles).
Then the lamp is removed and repaired in the workshop, and after repair the lamp is mounted in place. In damp rooms, the lamp body, the inside of the lamp, and the fixture mount are subject to corrosion. Therefore, moisture-proof lamps are used in damp and damp rooms.
5.2 Rules for working with electrified tools.
Before starting to work with the power tool, you must check:
Tightening the screws that secure parts of the power tool.
The serviceability of the gearbox by turning the spindle of the power tool by hand (with the electric motor turned off).
The condition of the power tool wire, the integrity of the insulation, the absence of broken wires.
Serviceability of the switch and grounding.
Power tools, step-down transformers, hand-held electric lamps and frequency converters are checked by external inspection. Attention is paid to the proper functioning of the grounding and insulation of the wires. The absence of exposed live parts and the compliance of the tool with operating conditions and supply circuit voltage.
Correct operation of an electrified tool is ensured by compliance with the established mode (avoid overheating to a temperature at which the palm of the hand cannot be placed on the body). During operation, it is necessary to monitor the condition of the lubrication of all components and replace it in a timely manner.
5.3 Work in electrical installations with voltages up to 1000 volts.
Work in switchgears and switchboards with voltages over 380 V can be carried out with complete voltage removal and the application of portable grounding. If it is impossible to relieve voltage in installations of 380 volts and below, work under voltage is allowed, but subject to strict compliance with the following requirements:
Work in dielectric galoshes or stand on an insulated base.
Use tools with insulating handles, and if they are not available, work with insulating gloves.
Protect adjacent live and grounded parts that are live.
Work in a hat and clothes with sleeves buttoned or tied with ribbons at the hands.
Bibliography:
1. V. B. Atabekov, M. S. Zhibov. "Installation of lighting electrical installations"
2. V.V. Meshkov, M.M. Epaneshnikov. "Lighting installations"
3. M. G. Lurie, L. A. Raitselsky, L. A. Tsiperman. “Design, installation and operation of lighting installations”
4. G.P. Egorov, A.I. Kovarsky “Design, installation, operation and repair of industrial electrical installations”
In case of insufficient lighting of production workshops Vision deteriorates, labor productivity falls, and the quality of products decreases. Therefore, for industrial enterprises, minimum illumination standards have been developed and are mandatory, provided for by SNiP and.
The illumination values according to these standards depend on the nature of production and the higher the greater the accuracy required when performing technological processes and production operations. When designing and lighting calculations, illumination is assumed to be slightly greater than required by standards.
This reserve is determined by the fact that during operation the level of initial (design) illumination inevitably decreases over time. This occurs due to a gradual decrease in the luminous flux of lamps, contamination of fittings and some other reasons. However, the illumination reserve taken during design and calculations is sufficient for normal operation of electric lighting installations: regular cleaning of lamps, light guides, timely change of lamps, etc. If the operation is unsatisfactory, the accepted supply of illumination cannot compensate for the decreasing level of illumination, and it becomes insufficient.
It should be kept in mind that The illumination of a room is greatly influenced by the color of the walls and ceilings and their condition. Painting in light colors and regularly cleaning from dirt helps to ensure the required lighting standards. The frequency of inspections of lighting electrical installations depends on the nature of the premises, the state of the environment and is established by the chief power engineer of the enterprise. Approximately for dusty rooms with an aggressive environment, the required frequency of inspection of working lighting can be taken once every two months, and in rooms with a normal environment - once every four months. For emergency lighting installations, inspection times are reduced by half.
Inspections of lighting installations
When inspecting lighting electrical installations, the condition of electrical wiring, panels, lighting fixtures, automatic devices, switches, plug sockets and other installation elements is checked. The reliability of the contacts in the installation is also checked: loose contacts must be tightened, and burnt contacts must be cleaned or replaced with new ones.
Replacing lamps in luminaires
In production workshops of industrial enterprises There are two ways to change lamps: individual and group. With the individual method, lamps are replaced as they fail; in the group method, they are replaced in groups (after they have served the required number of hours). The second method is more economically profitable, since it can be combined with cleaning the lamps, but is associated with a large consumption of lamps.
When replacing, do not use lamps of higher power than allowed for the lighting device. Excessive lamp power leads to unacceptable overheating of lamps and sockets and worsens the condition of wire insulation.
Lamps and fittings are cleaned of dust and soot in workshops with a small emission of pollutants (mechanical and tool shops, machine rooms, tanneries, etc.) twice a month; with large emissions of pollutants (forges and foundries, spinning factories, cement factories, mills, etc.) four times a month. Clean all elements of lamps - reflectors, lenses, lamps and outer surfaces of fittings. Windows for natural light are cleaned as they become dirty.
Workers and production shops are turned on and off according to a schedule only when natural light is insufficient to carry out work.
Inspections and tests of lighting installations during operation
During operation, electric lighting installations are subjected to a number of inspections and tests. Check the insulation resistance of working and emergency lighting. The serviceability of the emergency lighting system is checked by turning off the working lights at least once a quarter. The automatic switch or emergency lighting switch unit is checked once a week during the daytime. For stationary transformers with a voltage of 12-36 V, the insulation is tested once a year, and for portable transformers and lamps with a voltage of 12-36 V - every three months.
Photometric measurements of illumination in the main production and technological workshops and premises with monitoring of lamp power compliance with the design and calculations are carried out once a year. Illumination is checked using a lux meter in all production workshops and at main workplaces. The obtained illumination values must correspond to the calculated and design ones.
Before you begin checking the illumination, it is necessary to establish the places where it is advisable to measure the illumination. The results of inspections and checks are documented in acts approved by the chief power engineer of the enterprise. Features of operation of gas-discharge light sources
Features of the operation of fluorescent lamps and high-pressure gas-discharge lamps
The industry produces the following gas-discharge light sources with lamps:
- low pressure fluorescent mercury;
- high-pressure mercury arc (DRL type);
- xenon (DKsT type) high pressure air-cooled and ultra-high pressure water-cooled;
- high and low pressure sodium lamps.
The first two types of lamps are most widespread.
Gas discharge lamps have the following main features. The luminous efficiency (efficiency) of incandescent lamps is in the range of 1.6-3%, and their luminous efficiency does not exceed 20 lm/W of power consumption for high-power lamps and is reduced to 7 lm/W for lamps with a power of up to 60 W. The luminous efficiency of fluorescent lamps and DRL lamps reaches 7%, and the luminous efficiency exceeds 40 lm/W. However, such lamps are connected to the electrical network only through ballasts (ballasts).
It takes some time to light a fluorescent lamp and especially a DRL lamp(from 5s to 3 - 10 min). The main element of the ballast is usually an inductive reactance (reactor), which worsens; Therefore, they are used built into modern ballasts.
The industry produces general-purpose fluorescent lamps with power from 4 to 200 W. Lamps with a power from 15 to 80 W are mass-produced in accordance with GOST standards. The remaining lamps are manufactured in small batches according to the appropriate technical specifications. One of the features of using fluorescent lighting is that it is more difficult to find a fault compared to using incandescent lamps. This is explained by the fact that the most common circuit for switching on fluorescent lamps contains (ballast resistance) and becomes much more complex than the switching circuit for an incandescent lamp.
Another feature of fluorescent lighting is that For normal ignition and operation of a fluorescent lamp, the mains voltage should not be less than 95% of the nominal one. Therefore, when operating fluorescent lamps, it is necessary to control the network voltage. Normal operation of a fluorescent lamp is ensured at a temperature of 18-25 °C; at a lower temperature, the fluorescent lamp may not light up.
During operation, fluorescent lamps are inspected more often than incandescent lamps. It is recommended to inspect fluorescent lamps daily, and clean them from dust and check their serviceability at least once a month.
It is also necessary to take into account that after the end of the normal service life of a fluorescent lamp (about 5 thousand hours), it practically loses its quality and must be replaced. A lamp that only blinks or glows at one end must be replaced.
The first lanterns were oil-based. They were first lit in Russia on the streets of St. Petersburg in 1706 under Peter I on the anniversary of the victory over the Swedish invaders. Further, the lanterns were turned on on major holidays, and special workers were involved in their maintenance - filling containers with flammable substances, repairs, turning them on and off. With the death of the king, the tradition was safely forgotten.
Only several decades later, during the reign of Empress Anna Ioannovna, lanterns began to be installed on the central city streets again. For their maintenance, funds were allocated from the royal treasury for oil and the maintenance of responsible persons - lamplighters. But since oil was expensive, in order to save money, lanterns were rarely lit - only on dark, cloudy and moonless nights. In the society of that time it was believed that lighting was profitable. Many merchants were contracted to engage in this business, and the authorities rewarded those whose street lamps burned properly, and those who had a lot of them. For a long time, lanterns were lit from the beginning of August to the end of April.
By the end of the 18th - beginning of the 19th century in Moscow, many people began to illuminate the entrances of houses and approaches to them on their own - with the help of bottles with burning oil. Cathedrals and Kremlin walls were illuminated in the same way, and then shop windows, approaches to banks and organizations. With the advent of kerosene lanterns, government officials again took responsibility for lighting cities. In the 70s of the 19th century, when Alexander Ladygin invented the vacuum bulb, the first street lamps with incandescent lamps were lit on Odesskaya Street in St. Petersburg.
A lot has changed in the 20th century. The lighting system and its maintenance have improved significantly. Recently, the government has taken full responsibility for the maintenance of lighting in streets and public areas, but companies and individuals are also allowed to install and maintain lighting fixtures to provide additional illumination to their facilities.