Coefficient of demand for electrical equipment: table. Equipment for industrial enterprises

It's not a secret that industrial enterprises always have a huge number of different electrical appliances - it is through them that activities are carried out in shops, factories, in all firms. And the further the progress is, the more electronics is used to cover absolutely all possible areas of activity. And most people who work in offices, in factories, in general at enterprises, do not think that they constantly use different devices to achieve their goals. Naturally, why should they think about this, because they have their own tasks, and devices for them are just tools. However, if you think about what is behind all machines and devices in production, you can immediately marvel at what a variety of different devices, connected with each other, constantly operating under different voltages, can be in the same room. And after all, they are not just there - they turn on, turn off, work without interruptions or with interruptions, at various capacities. Even at home, you can, without hesitation, turn on the kettle, microwave oven with computers working, but you can do this for the reason that someone in advance correctly planned everything so that network congestion did not occur when switching on a large number of electrical appliances. As for production, we can say the same here - but it should be noted that planning in this case is made on a more impressive scale. In planning, it is necessary to take into account a huge number of various factors, one of the most important is the demand coefficient of electrical equipment. The table for this coefficient will be analyzed in detail in this article. However, to begin with, you need to understand that this coefficient as a whole is of itself, how it is calculated and how it is used. This is a very important parameter when connecting electrical systems, so you should carefully consider the demand coefficient of electrical equipment, the table by experienced electricians should also be actually learned by heart.

Determination of coefficient

Many novice electricians suffer greatly from the fact that they can not understand for themselves what exactly is the demand coefficient of electrical equipment, the table for them does not make any sense, since it simply lists the devices and some numbers. So what is the given coefficient? To begin with, you just need to familiarize yourself with its definition - of course, it may not immediately seem clear to you, but as you read this material, you will understand more and more. So, the demand coefficient of electrical equipment (the table on it will be considered separately, now only theory is taken into account) is the ratio of the combined maximum load of energy receivers to their total installed capacity. The definition is quite capacious, however, as it was said before, it is not immediately possible to understand what its essence is all about - it is simply impossible to understand how the electrical equipment demand coefficient is used in one sentence. The table does not help you to understand the question, so it's worthwhile to postpone its consideration at a later time. Now we just need to try to understand the essence of this concept.

The essence of the coefficient

In order to better understand the essence of this coefficient, you need to imagine the production - there are different devices, such as a variety of machines, industrial fans and so on. All these devices consume electricity, therefore, when designing the power grid, it is necessary to find out what the power of the generator should be, so that all available receivers receive the required amount of current. The power should not be too small, otherwise it will not be enough for all devices, and should not be too large - this will lead to over-expenditure. Thus, there is a demand coefficient, which allows electricians to determine what will be the actual energy consumption of the device, compared to the installed capacity. Simply put, thanks to the demand factor, you can get a calculated one from the installed capacity , which can already be used in practice. All devices have their own demand factor - the aforementioned industrial fans, furnaces, overpasses and so on. However, it should be noted that the table of demand coefficients, which has already been mentioned more than once, practically does not contain indicators for specific devices. It contains data on specific industries and workshops, which are often part of this production. But before proceeding to a detailed examination of this table, it is necessary to understand one more point - where does this coefficient come from?

The origin of the coefficient

Many people can ask the question - what is the demand coefficient of electrical equipment? Molding machines have it, for molding shops it is also available, but what is behind it? After all, the power of electrical equipment is clear to everyone, this is a very real value that exists in reality. But the coefficient is just a number, where does it come from? The fact is that all coefficients are contained in specialized reference materials - those same tables, about which much has already been said at the very beginning of the article. And they were determined during the operation of various electrical appliances, as well as from the experience of functioning of entire plants and workshops. Thus, specialists for a long time observed how molding machines work, for example, recorded data, conducted calculations, and after a while announced what kind of demand they had. And this value was taken as the norm, entered in the official tables and placed in the reference materials, which now use electricians. Well, this is all the theoretical knowledge that you should have - now you understand what the given coefficient is, what it affects, and where it comes from. And this means that the variety of different figures in the table of demand factors for you will not be something unexpected and incomprehensible. Therefore, you can safely proceed to the next part of the article, where some of the items in the table of demand coefficients will be disassembled. Completely the table, naturally, will not be dismantled, since it has so many sections - more than twenty different types of production, for each of which a certain number of shops are allocated.

Workshops for general industrial use

The very first section does not include construction equipment or any highly specialized shops, since it is basic. Here we consider those shops and buildings that are used everywhere, rather than specialized production. For example, here you can find the demand coefficient of electrical equipment in the block of main shops - it is equal to 0.4-0.5. This value, at first glance, may seem small, but in fact it is quite normal - in the course of the table you will see much smaller values of this coefficient. For example, even in this section there are low coefficients - for example, for the same block of auxiliary shops it does not exceed 0.35. If you take the highest coefficient in this section, you can find it at the shops of thermal load, where heating furnaces work. In many respects due to them the indicator in this workshop is so high - 0.7-0.8. Now you get the first idea of how the section of the table as a whole looks - regardless of whether the construction equipment, smelting shops or anything else is described there, a section will be highlighted in the table, in which the shop names will be placed. And opposite these names will be shown the approximate demand coefficient of electrical appliances of this shop. Therefore, electricians now, with the organization of electrical wiring and electrical supply in the workplace, do not have to determine by scientific shock, trial and error every type of demand for specific electrical appliances of a particular shop - they have average values that can be relied on in their work.

Copper smelters

This is the first specialized plant, which is indicated in the coefficient table. And immediately you can pay attention to the fact that it has very few items - only two. The fact is that most of the shops of the smelter have already been examined in the first section, so there is no point in repeating the same workshops here. That is, it turns out that the electrician is always worth first of all to view the first section with the shops of general industrial purpose, and then to search for a more specialized section. But the fact that it is specialized does not mean that the items in it will not imply the use of common equipment - for example, electric hoists are found in many copper refining shops (the coefficient of devices is 0.6), and it is also taken into account when calculating the coefficient. The second point of this section is the water jacket and reflecting furnaces, their coefficient is slightly lower than the previous point - 0.5. There are also devices of general purpose, such as electric hoists - now you should have finally grasped the essence of the table, so there is no point in recalling such moments in the future.

Non-ferrous metallurgy plants

In this section, you can find one of the lowest scores in the entire table. Despite the fact that there are often installed very demanding electric drums, the laboratory at the non-ferrous metallurgy plant has a demand coefficient of only 0.25. But do not think that throughout the plant there are no energy-intensive shops and premises. For example, the electrolysis shop has an index of 0.7, which is quite a lot. And here, even drying drums are not needed to achieve this. In general, it is necessary to take into account very many aspects to accurately indicate the correct demand coefficient, with which electricians can then work.

Plants of ferrous metallurgy

It would seem that both plants are engaged in metallurgy, but in the previous section, non-ferrous metallurgy was described , and in this - black. However, in this case the workshops (and the devices in them, respectively) are completely different - and have absolutely different coefficients of demand for electrical equipment. First of all, a cold- rolled mill with a 0.4-0.5 index is indicated. The vacuum pump installed in the blast furnace shop consumes a lot of energy, so the coefficient is quite high - 0.45. But the most important thing that is worth noting in this section is that it is impossible to single out any items with a very high or very low coefficient. The indicators for the whole section do not drop below 0.4 and do not rise above 0.6, and this is taken into account both by the vacuum pump and other similar devices used in this type of production.

Concentrating plants

It is worth a little distraction from the topic and think about a portable power tool - is it included in this table? Pay attention to the fact that the majority of devices that are considered within a particular production department can consume simply incredible amounts of electricity - so these kinds of tools are most often either not considered, or included as a small error. Returning to the topic, in the new section the coefficient diversity becomes a bit wider - however not as much as, for example, in the first section, where you could meet the figures from 0.2 to 0.8. The first in the list, naturally, is the main enrichment shop - and it has practically the highest coefficient in production, 0.6-0.65. Above the indicator only in the flotation shop - 0.6-0.7. As for the lowest, here is a gold recovery shop with a coefficient of 0.4 - as you can see, in this production in all shops, a serious supply of electricity is required, from which the engine, generators and other devices will start to operate all the machines in the shop.

Agglomeration factories

In such a factory, the main thing is the sintering shop - but its coefficient is absolutely not distinguished by the others, 0.5. It is possible to distinguish here only the overload shop where there are no welding machines or any other energy-consuming equipment, so the demand coefficient here is much lower - 0.3-0.4. Naturally, there are other shops here, however, they are already slightly higher - often there is a conveyor, belt conveyor or other similar devices that work constantly and require serious current costs.

Heavy Engineering Plants

Separately, it is worth paying attention to factories, in which there are really many different shops and divisions. As you can see, if you study reference materials, in many previous cases the number of workshops does not exceed even five and certainly is not greater than ten. In the case of heavy engineering plants, everything is a little different - there is an impressive number of items that are worth considering separately. And among them you can find such shops, where the coefficient is high enough, and also those where it is extremely low. Again, there will not be considered individual devices, such as welding transformers, semiautomatic machines, here you will find out only the demand coefficients of electrical devices within the individual shops. The most important in such production is considered the main building - it is quite possible to understand by name. Here the coefficient is not very high - only 0.3-0.4, but there are also departments with less outstanding indicators. For example, you can take a flyover where the figure is only 0.25, or even an experimental workshop, where there is not much equipment, and it is not very expensive (can a lot of energy consume electrostatic precipitators for cleaning gases?). Therefore, it is not surprising that this workshop has a demand factor of only 0.2. As for the highest index in the list of this section, it is impressive only against the background of the others. The demand factor of 0.6 at the plant of heavy engineering has a lacquer shop, near it there is one more item - the insulating department. Here the coefficient can also be 0.6, but it can also be less - up to 0.5, so the designation in the table is different - 0.5-0.6. In various shops there are various metalworking machines (equipment), and each of them had to be taken into account to create such a vast and very important for the electricians table.

What's next?

Naturally, the table of demand coefficients of electrical equipment does not end there - there are many more sections covering the most diverse spheres of activity and industry. But you should also learn some details about what else you can do with the demand factor. You already know that with its help you can determine the estimated and nominal (that is, installed) capacity of both electrical devices and workshops in general. But there is also a formula that allows you to recognize other factors, such as utilization rate and maximum - they also play an important role in the calculation and planning of electrical systems. Simply put, the demand factor is one of the most important parameters in the calculation and design of power supply systems and installations. If you are an electrician, then you need to know the basic demand factors, and also have constant access to relevant reference materials. Then for you it will not be the slightest problem to provide electricity to any object - this is what determines the professional of his business. Be able to use tables and other materials, not just your hands! You should understand perfectly well that this coefficient is not the only theoretical indicator that exists in the world - with two other coefficients, use and maximum, you have already met briefly, but there are a lot of similar values, and each of them plays an important role, supplementing The big picture. Therefore, do not neglect theoretical knowledge, as often they are even more important than practical ones. That is why the demand coefficient of electrical equipment is so important.