What is static charge. Static electricity and protection against it

It can occur on insulated conductors, on the surface or in the bulk of dielectrics.

The friction that occurs when two substances of different kinds come into contact leads to the electrification of dielectrics. This is due to different molecular and atomic forces. We can say that static electricity is obtained when their equilibrium is disturbed due to the acquisition or loss of an electron.

This process is very easy to explain. The state of equilibrium of an atom is achieved when there are the same number of protons and electrons. Moving from one atom to another, electrons form positive and negative ions. With their imbalance, static electricity occurs.

Protons and electrons have the same electrical charge, but with different polarities. It is measured in pendants and determines the amount of electricity that passes in 1 second. in the cross section of the conductor. The static charge is directly proportional to the number of unstable ions, that is, the deficit or excess of electrons.

Static electricity is capable of being generated. This is due to the absence of one electron in the positive ion, as a result of which it can receive a free electron from the negative particle. In turn, a negative ion can be an atom or a molecule with a large number of electrons. In these cases, there is one electron that can neutralize the positive charge.

The main causes of static electricity are:

• distance or contact of two materials;
• fast temperature drops;
• UV radiation, radiation, strong electric fields,;
• cutting operations (cutting machines or paper cutting machines);
• guidance, that is, the generation of an electric field caused by a static charge.

The phenomenon called static electricity is ubiquitous in everyday life. Electrostatic discharge occurs at very high voltages, but at low currents. In this case, there is no danger to humans.

Despite this, protection against static electricity is necessary, as it can be dangerous to many elements of electrical appliances. It often affects transistors, microprocessors, circuits, etc. When working with electronic components, measures must be taken to prevent the build-up of static charges.

A direct danger exists with lightning arising during the formation of thunderclouds. Clouds due to the movement of air currents, which are saturated with water vapor, can also form such discharges often occur between charged clouds and the earth. In this case, you need protection against static electricity in the form of lightning rods. They are capable of delivering a discharge straight into the ground. In addition to lightning, a thundercloud creates dangerous electrical potentials on insulated metal objects due to the process

The lungs resulting from various manifestations of static electricity are harmless at first glance, but this is far from the case. This phenomenon can hide in itself a great danger, since the spark that occurs can cause a fire. Static electricity and protection against it are two concepts that should be known to everyone, since sometimes serious troubles happen due to ignorance.

In everyday life and at work, it is necessary to prevent the occurrence of this type of electricity. To do this, it should be carried out regularly. Flammable liquids - this is another serious threat. They should be used in well-ventilated areas to partially prevent static electricity (and are almost guaranteed protection against static electricity). When handling such liquids, use natural clothing, grounding rotating machinery, and only metal containers for storing flammable liquids.

Origin

Electrization of dielectrics by friction can occur when two dissimilar substances come into contact due to the difference in atomic and molecular forces (due to the difference in the work function of an electron from materials). In this case, a redistribution of electrons (in liquids and gases also ions) occurs with the formation of electrical layers with opposite signs of electric charges on the contacting surfaces. In fact, atoms and molecules of one substance, which have a stronger attraction, rip electrons from another substance.

On the other hand, such voltages can be dangerous for the elements of various electronic devices - microprocessors, transistors, etc. Therefore, when working with electronic components, it is recommended to take measures to prevent the accumulation of static charge.

Lightning

As a result of the movement of air flows saturated with water vapor, thunderstorm clouds are formed, which are carriers of static electricity. Electrical discharges are formed between opposite charged clouds or, more often, between a charged cloud and the ground. When a certain potential difference is reached, a lightning discharge occurs between clouds or on the ground. To protect against lightning, lightning rods are installed that conduct the discharge directly into the ground.

Notes (edit)

see also

Links

• Electrical encyclopedia # 143. War with "static" in the car and at home
• ESBE. Article

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See what "Static electricity" is in other dictionaries:

Static electricity- see Electricity, static ...

STATIC ELECTRICITY, a certain amount of ELECTRIC CHARGES at rest, not movement, as is the case with ELECTRIC CURRENT. As a rule, uncharged ATOMS have the same number of positive and negative ELECTRONS. ... ... Scientific and technical encyclopedic dictionary

static electricity- 3.1 static electricity: A set of phenomena associated with the separation of positive and negative electric charges, conservation and relaxation of free electrostatic charge on the surface or in the bulk of dielectrics or on ... ... Dictionary-reference book of terms of normative and technical documentation- (Electricity) The concept of electricity, the receipt and use of electricity Information about the concept of electricity, the receipt and use of electricity Content is a concept that expresses the properties and phenomena due to the structure of physical ... ... Investor encyclopedia

Noun., P., Upotr. cf. often Morphology: (no) what? electricity, what? electricity, (see) what? electricity than? electricity, about what? about electricity 1. Electricity is a type of energy that people use to bring in ... ... Explanatory dictionary Dmitrieva

- (from the Greek. elektron amber, as amber attracts the lungs of the body). A special property of some bodies, which manifests itself only under certain conditions, for example. friction, heat, or chemical reactions, and revealed by the attraction of the lungs ... ... Dictionary foreign words Russian language

ELECTRICITY STATIC- a set of phenomena associated with the emergence, conservation and relaxation of a free electric charge on the surface (or in the volume) of dielectrics or on insulated conductors. Charges of static electricity (ES) are formed at the most ... ... Russian encyclopedia on labor protection

The concept of static electricity is familiar to everyone from the school physics course. Static electricity arises in the process of the appearance of charges on conductors, surfaces of various objects. They appear as a result of friction that occurs when objects come into contact.

What is static electricity?

All substances are made up of atoms. The atom has a nucleus around which electrons and protons are located in the same number. They are able to move from one atom to another. When moving, negative and positive ions are formed. Their imbalance leads to the fact that there is static. The static charge of protons and electrons in an atom is the same, but has a different polarity.

The static appears in everyday life. Static discharge can occur at low currents but high voltages. There is no danger to people in this case, but the discharge is dangerous to electrical appliances. During the discharge, microprocessors, transistors and other circuit elements suffer.

The causes of static electricity

Static occurs under the following conditions:

• contact or distance from each other of two different materials;
• sudden changes in temperature;
• radiation, UV radiation, X-rays;
• the operation of the paper cutting machine and cutting machines.

Static often occurs during or before a thunderstorm. Thunderclouds create static electricity when they move through moisture-laden air. The discharge occurs between cloud and ground, between individual clouds. The device of lightning rods helps to conduct the charge into the ground. Thunderclouds create electrical potential on metal objects, causing light bumps when touched. For a person, a blow is not dangerous, but a powerful spark can cause the fire of some objects.

Each resident has repeatedly heard the crackling sound that is heard when removing clothes, a blow from touching the car. This is a consequence of the appearance of static. An electrical discharge is felt when cutting paper, combing hair, and pouring gasoline. Free charges accompany a person everywhere. The use of various electrical devices increases their appearance. They arise when pouring and crushing solid products, pumping or pouring flammable liquids, when transporting them in tanks, when winding up paper, fabrics and films.

The charge appears as a result of electrical induction. Large electrical charges are generated on metal car bodies during dry seasons. A TV screen or computer monitor is capable of being charged by exposure to a beam generated in a cathode-ray tube.

The harm and benefits of static electricity

Many scientists and inventors have tried to use a static charge. Bulky units were created, the benefits of which were low. The discovery of corona discharge by scientists turned out to be useful. It is widely used in industry. Using an electrostatic charge, complex surfaces are painted, gases are purified from impurities. This is all well and good, but there are numerous problems. Electric shocks are powerful. They can sometimes hit a person. This happens both at home and in the workplace.

The harm of static electricity is manifested in shocks of different power when removing a synthetic sweater, when leaving a car, turning on and off a food processor and vacuum cleaner, laptop and microwave oven. These blows can be harmful.

Static electricity is generated, which affects the functioning of the cardiovascular and nervous systems. One should defend against it. The person himself is also often a carrier of charges. When in contact with the surfaces of electrical appliances, they are electrified. If it is a control and measuring device, the case may end in its breakdown.

The discharge current brought by a person destroys the connections with its heat, breaks the microcircuit tracks, destroys the film of field-effect transistors. As a result, the circuit becomes unusable. Most often, this does not happen immediately, but at any stage during the operation of the instrument.

In enterprises that process paper, plastics, textiles, materials often behave incorrectly. They stick to each other, stick to different types equipment, push off, collect a lot of dust on themselves, wind up incorrectly on spools or bobbins. This is due to the generation of static electricity. Two charges of the same polarity repel each other. Others, one of which is positively charged and the other negatively charged, attract. Charged materials behave the same way.

Fire can occur in printing plants and other locations where flammable solvents are used. This occurs when the operator is wearing non-conductive shoes and the equipment is not properly grounded. The flammability depends on the following factors:

• discharge type;
• discharge power;
• a source of static discharge;
• energy;
• presence of solvents or other flammable liquids nearby.

Discharges are spark, brush, sliding brush. A spark discharge emanates from a person. The carpal arises on the sharpened parts of the equipment. Its energy is so low that it practically does not cause a fire threat. Sliding brush discharge occurs on synthetic sheets, as well as on roll materials with different charges on each side of the canvas. The danger it poses is the same as a spark discharge.

Lethality is a major issue for safety professionals. If a person holds on to the bobbin and is in the tension zone himself, his body will also be charged. To discharge the charge, be sure to touch ground or grounded equipment. Only then will the charge go into the ground. But in this case, a person will receive a strong or weak electric shock. As a result, reflex movements occur, which sometimes lead to injury.

Prolonged stay in the charged zone leads to a person's irritability, to a decrease in appetite, and poor sleep.

Dust from the production area is removed by ventilation. It collects in pipes and can be ignited by static sparking.

How to remove static electricity from a person

The simplest means of protection against it is equipment grounding. In production conditions, screens and other devices are used for this purpose. In liquid substances, special solvents and additives are used. Antistatic solutions are actively used. These are substances with low molecular weight... The molecules in the antistatic agent move easily and react with moisture in the air. Due to this characteristic, static is removed from a person.

If the operator's shoes are on non-conductive soles, it is imperative that the operator touch ground. Then the escape of the static current into the ground cannot be stopped, but the person will receive a strong or weak blow. We feel the effect of a static current after walking on carpets and rugs. Electric shocks are received by drivers getting out of the car. It is easy to get rid of this problem: just touch the door with your hand while sitting still. The charge will drain into the ground.

Carrying out ionization helps a lot. This is done using an anti-static bar. It has many needles made of special alloys. Under the influence of a current of 4-7kV, the air around it decomposes into ions. Air knives are also used. They are an anti-static bar through which air is blown in and cleans the surface. Static charges are actively generated when liquids with dielectric properties are sprayed. Therefore, to reduce the action of electrons, the falling jet must not be allowed.

It is advisable to use antistatic linoleum on the floor and to clean more often with household cleaning products. In enterprises related to the processing of fabrics or paper, the problem of getting rid of statics is solved by wetting the materials. The rise in humidity prevents harmful electricity from building up.

To remove static, you must:

• humidify the air in the room;
• treat carpets and rugs with antistatic agents;
• wipe the seats in the car and in the rooms with antistatic wipes;
• moisturize the skin on yourself more often;
• give up synthetic clothing;
• wear leather-soled shoes;
• prevent the appearance of static on the laundry after washing.

Indoor flowers, a boiling kettle, and special devices moisten the atmosphere well. Antistatic compounds are sold in household chemical stores. They are sprayed over the carpet surface. You can make an antistatic agent yourself. To do this, take a fabric softener (1 cap), pour it into a bottle. Then the container is filled with clean water, which is sprayed over the surface of the carpet. Anti-static wipes neutralize the charges on the seat upholstery.

The skin is moisturized with a lotion after a shower. Hands are rubbed several times a day. You should change clothes for natural. If charged, treat with antistatic agent. It is recommended that you wear leather-soled shoes or go barefoot around the house. Before washing, it is advisable to sprinkle ¼ glasses of baking soda (baking soda) on clothes. It removes electricity shocks and softens fabrics. When rinsing the laundry, you can add vinegar (¼ glass) to the machine. It is better to dry your laundry in the fresh air.

All of the above measures help neutralize static problems.

Static electricity is a collection of electrical charges on the surface of a material, usually insulators. This electricity is therefore called static because there is no current flowing, as usual - alternating or direct current... To understand static electricity, you need to understand the basics of atoms and magnetism. All physical objects are made of atoms. Inside the atom are protons, electrons and neutrons. Protons are positively charged, electrons and neutral neutrons are negatively charged.

Typically, two materials participate in static electricity, one having an excess of electrons or negative (-) charges on its surface, and another material having an excess of positive (+) electrical charges. Atoms on the surface of a material that have lost one or more electrons will have a positive (+) electrical charge, have acquired a negative (-).

Causes of static electricity

Static electricity is usually generated when certain materials are rubbed against each other - like wool on plastic or shoe soles on carpet. This phenomenon also occurs when materials are pressed against each other.

A material that loses electrons acquires an excess of positive (+) charges. The material that receives electrons receives an excess of negative (-) charges on its surface. Static electricity is generated much better when the air is dry or low humidity. When the air is humid, water molecules can collect on the surface of various materials. This can prevent the build-up of electrical charges. It has to do with the shape of the water molecule and its own electrical forces. But when there is extreme turbulence between water droplets, such as in a thunderstorm cloud, static electrical charges can build up on the water droplets. Benjamin Franklin, using flying kites during a storm, showed that static electricity is also generated in a cloud during a thunderstorm.

Static electricity properties

Static electricity can attract or repel each other's materials. It can also cause sparks when moving from one material to another.

A typical example of static electricity is small electricity that can be felt when the doorknob is touched during dry weather.

Static electricity is generated when additional electrons (negatively charged particles) accumulate and are dumped.

This type of electricity does not move through wires, but accumulates on the surface and transfers charges from one element to another. Popular demonstrations of this usually involve rubbing hot air balloon over fabric, such as corduroy pants, and then place the ball next to a wall where the ball itself can stick.

The existence of a person in a specific environment is associated with the impact on him (and on the surrounding conditions) of electromagnetic fields. What conclusion can be drawn in the presence of stationary charges? This means that we are talking about electrostatic fields.

The main danger

In this case, the nervous system of people is under great stress. This is due to the fact that electric fields from an excess amount of charges affect the body, clothing and objects. The cardiovascular system of the body also reacts to these phenomena.

basic information

What is static electricity? It occurs when there is a violation of intramolecular or atomic equilibrium. This is due to the loss or acquisition of an electron. Normally, an atom is characterized by an equilibrium state. This is due to the equal number of negative and positive particles. We are talking about electrons and protons. The former easily move from one atom to another. In this case, the formation of negative and positive ions occurs. Thus, static electricity is generated when such an imbalance occurs.

The main reasons for the appearance

Static electricity can be caused by a number of factors, among which are the following:

More about the dangers

Electrification of various materials can be hazardous to people. In this regard, everyone needs to know the rules of protection against static electricity. The main danger is the possibility of sparking. This applies to both an insulated conductive object and an electrified surface.

Possibility of discharge

This occurs when the strength of the corresponding field above the surface of the conductor or dielectric (due to the accumulation of charges on them) has reached a critical value. The latter is sometimes called disruptive. This value for air is approximately 30 kV / m.

Other hazards

Spark discharges can ignite combustible mixtures. This will happen when the released energy is greater than that which contributed to the start of the fire. There is also total value... This energy must be higher than the same minimum ignition parameter of the combustible mixture.

Possible consequences

Why do you need to know the basic rules of protection against static electricity? In some cases, unwanted nervous and painful sensations may arise from its effects. Sometimes this leads to an involuntary sharp movement of a person. As a result, he may receive any mechanical injury. In this case, a person's own static electricity plays an important role.

Control features

There is a corresponding GOST. Static electricity can indeed be extremely dangerous. To reduce the risks, the permissible levels of the intensity of the corresponding fields have been established. All this must be tightly controlled in the workplace. It is also necessary to comply with sanitary and hygienic standards. These requirements apply to fields that arise from the electrification of certain materials, as well as during the use of installations. In the latter case, a high DC voltage is implied. Compliance with these is the main protection against static electricity. GOST defines the permissible levels of tension in the workplace. Also there are registered General requirements to protective equipment and control. As for the permissible levels of electric field strength, they are set taking into account the time spent by employees at the workplace.

Choosing the right products

Static electricity protection can be arranged different ways... First of all, you need to take into account the following:

1. Features of technological processes.
2. The microclimate of the premises.
3. Physicochemical properties of the processed materials.

Thus, an approach to the organization of safety measures is being developed. Removal of static electricity can be implemented in several ways:

1. Elimination of the generated charges.
2. By decreasing their intensity.

Concerning last case, then the answer to the question of how to remove static electricity is as follows: this is achieved by reducing the force and speed of friction, increasing the conductivity of materials and differences in their respective properties. The following are practical guidelines:

The most effective methods

Charges can form when certain liquids are splashed, sprayed and splashed. Ideally, when such phenomena will be completely eliminated. If this is not possible, then you need to at least limit them as much as possible. For example, when filling tanks with dielectric fluids, a freely falling jet cannot be used. In this case, the drain hose is guided along the wall in order to avoid splashing. Ideally, if it is possible to lower it under the liquid level. The lower the electrical conductivity of materials, the higher the rate of charge formation. Thus, it is desirable to increase the previously specified parameter of the existing elements. This can be done by introducing antistatic suction cups. Accordingly, special linoleum should be used to cover the floors. Periodic antistatic treatment of carpets is highly desirable. This also applies to synthetic fabrics. It is desirable that the contacting substances and objects are made of similar materials. In this case, contact electrification is also excluded. For example, polyethylene powder should be stored in barrels made of similar materials. It is better to transport and transfer it only using the appropriate pipeline and hose. In some cases, this is not possible. Then it is permissible to use materials that are close in dielectric properties. So, we can draw a small conclusion that for protection against static electricity, the use of weak or non-electrifying materials is necessary. You also need to strive to eliminate the following phenomena in the work with dielectric fluids:

1. Splashing.
2. Splashing.
3. Spraying.
4. Friction.

If there is no possibility of complete elimination, then you need to at least limit them as much as possible.

Additional ways

Humid air has sufficient conductivity so that the resulting charges can drain through it. Thus, they practically do not arise in the corresponding environment. Therefore, humidifying the air is the most common and easiest way to deal with static electricity. There are other security methods as well. It is about ionizing the air. It is also a common method of dealing with electrical charges. The fact is that ions help to neutralize them. They are produced by a special device. A household ionizer has many advantages. First of all, it helps to improve the air ion composition air environment premises. This eliminates electrical charges that arise on clothing, synthetic surfaces and carpets. As far as production is concerned, the most powerful ionizers are used there. Meet various designs... However, electric ionizers are the most common.