Capacitor - what is this device? Capacitor charge
In the electrical circuit of each device there is such an element as a capacitor. This it serves to fill with the energy that is needed for the proper and uninterrupted operation of the equipment.
What is a capacitor
Each capacitor is a device that has a set of technical parameters that should be considered in detail.
Capacitors can be found in many branches of electrical engineering. Their immediate scope:
- Creating chains, oscillatory circuits.
- Getting a pulse with more power.
- In industrial electrical engineering.
- In the manufacture of sensors.
- Improving the performance of protective devices.
For each capacitor, the main parameter is its capacity. Each device has its own and it is measured in Farad. At the heart of electronics and radio use capacitors with a millionth Farad. To find out the nominal capacity of the device, it is enough to look at its body, which has all the information.Capacity readings may vary due to the following parameters:
- The total area of all the plates.
- The distance between them.
- The material of which the dielectric is made.
- Ambient temperature
Along with the nominal capacity, there is also a real one. Its value is much lower than the previous one. By actual capacity, you can determine the basic electrical parameters. Capacity is determined by the charge plate and its voltage. The maximum capacity can reach several dozen farads. The capacitor can also be characterized by specific capacity. This is the ratio of the capacitance and volume of the dielectric. The small thickness of the dielectric provides a large value of the specific capacitance. Each capacitor can change its capacity, and they are divided into the following types:
- Permanent capacitors - they practically do not change their capacity.
- Variable capacitors - the capacitance value changes during the operation of the equipment.
- Trimmer Capacitors - change their capacity from the adjustment of the equipment.
Voltage is considered another important parameter. In order for the capacitor to perform its functions in full, you need to know the exact voltage reading. It is indicated on the device case.Rated voltage depends on the complexity of the design of the capacitor and the basic properties of the materials used in its manufacture. The voltage applied to the capacitor must be exactly the same as the rated voltage. Many devices heat up during operation, in which case the voltage drops. Often, due to a large voltage difference, the capacitor may burn out or explode. This is also due to leakage or increased resistance. For the safe operation of the capacitor it is equipped with a safety valve and a notch on the body. As soon as there is an increase in pressure, the valve opens automatically, and the body breaks down according to the intended incision. In this case, the electrolyte exits the condenser in the form of a gas and there is no explosion.
The simplest capacitor is two electrodes, made in the form of plates, which are separated by thin insulators. Each device has a deviation that is permissible during its operation. This value can also be found by marking the device. Its tolerance is measured and indicated as a percentage and may lie in the range from 20 to 30%.For electrical engineering, which should work with high precision, you can use capacitors with a small tolerance value, not more than 1%.
The above parameters are essential for the operation of the capacitor. Knowing their values, you can use capacitors for self-assembly of machines or machines.
Types of capacitors
There are several main types of capacitors that are used in various techniques. So, it is worth considering each species, its descriptions and properties:
- Electrolytic capacitors. Devices of this type have a large capacity. Available in compact size and light weight. The plates in the amount of two pieces are made of foil and a thin layer of matter impregnated with electrolyte. This allows you to serve as a good guide. Electrolytic capacitors have two terminals: positive and negative. A prerequisite for proper connection is respect for polarity.
- Paper or plastic capacitors. They are made, as a rule, in the form of a roll made of foil with a dielectric. Most often in the schemes use plastic devices, as they have greater resistance than paper ones. Such capacitors of the small sizes and small weight are produced.Devices can be low-voltage and high-voltage.
- Disc capacitors made of ceramic. Cheap analogues of devices that have high endurance and reliability. The capacitor ICF is found in every electronic circuit. Such types are suitable for work in devices with signals that change polarity.Multilayer ceramic capacitor works only at high frequencies. Only such devices have low current loss, compact size, low weight and low cost.
- The capacitor is variable. Available in various shapes and sizes. When installing such a device requires only an experienced technician who understands such capacitors. Available in the form of mounted and printed wiring, as well as for microcircuits and micromodules.
- The vacuum condenser. The dielectric is the vacuum itself. Its electrodes are placed in a glass case with a vacuum.
- Capacitors with gaseous dielectrics. These include devices with air or gas filled dielectrics.
- Capacitor with liquid dielectric. As a rule, these are organic liquids, which include silicon or sovol, as well as mineral and petroleum oils.
- Capacitors with glass, resin, combined dielectric.They are divided into three subgroups: low-voltage, high-voltage, and interference suppression. Its lining is made of a thin layer of metal that is applied to the dielectric in the form of a thin foil.
Each capacitor has its own purpose, so they are additionally classified into general and special. Common capacitors are used in all types and classes of equipment. These are mainly low-voltage devices. Special capacitors are all other types of devices that are high-voltage, pulsed, starting, and various other types.
Features of a flat capacitor
Since a capacitor is a device intended for voltage accumulation and its further distribution, therefore, it is necessary to choose it with good electrical capacity and “breakdown” voltage. One of these is a flat capacitor. It is produced in the form of two thin plates of a certain area, which are located at a close distance from each other. Flat capacitor has two charges: positive and negative.
The plates of a flat capacitor among themselves have a uniform electric field.This type of device does not interact with other devices. The capacitor plate is able to amplify the electric field.
The correct charge of the capacitor
It is a repository for electrical charges, which must be constantly charged. The capacitor is charged by connecting it to the network. To charge the device, you need to properly connect it. To do this, take the circuit, which consists of a discharged capacitor with a capacitor, a resistor, and connect to the power supply with a constant voltage.
The capacitor is discharged according to the following type: the key is closed, and its plates are interconnected. At this time, the capacitor discharges, and between its plates the electric field disappears. If the capacitor is discharged through the wires, then it will take a lot of time, since they accumulate a lot of energy.
Why do I need a capacitor circuit
In the circuits are capacitors, which are made of a pair of plates. For their manufacture take aluminum or brass. Good work of radio engineering depends on the correct setting of the circuits. The most common circuit circuit consists of a single coil and a capacitor, which are closed together in an electrical circuit.There are conditions that affect the appearance of oscillations, so most often the capacitor circuit is called oscillatory.
A capacitor is a passive device in an electrical circuit that is used as a container for storing electricity. In order for the means for the accumulation of energy in electrical circuits, called a capacitor, to work for a long time, you must follow the specified conditions, which are written on the device case. The scope is wide. Use capacitors in electronics and various equipment. Devices are subdivided into many different types and come in various designs. Capacitors can be connected in two types: parallel and serial. Also on the case of the device there is information about the capacity, voltage, tolerance and its type. It is worth remembering that when connecting a capacitor it is necessary to observe the polarity. Otherwise, the device will quickly fail.