Where are transformers generally used?

Transformer is generally used for the measurement and metering of current and voltage. It works on the principle of electromagnetic induction. That is, the current and voltage that are proportional to the primary side and suitable for measurement are induced on the secondary side by electromagnetic induction.

Transformer is mainly divided into current transformer and voltage transformer, which is used to convert current or voltage proportionally

Measure the voltage and current in an AC circuit, or control the switch when the power is off.

The transformer is mainly divided into current transformer and voltage transformer, the role is to reduce the current or voltage in a certain proportion, generally used for the measurement of electric energy, its principle is similar to the transformer.

The current transformer is mainly used in places where the current to be measured is greater than the range of the ammeter.

1. The principle of current transformer is based on the principle of electromagnetic induction. A current transformer is made up of a closed core and windings. It has a small number of turns on the primary side winding and is strung in the line where the current needs to be measured.

2. Therefore, it often has all the current of the line flowing through, the number of turns of the secondary side winding is more, and it is connected in series in the measuring instrument and the protection circuit, and when the current transformer is working, its secondary side circuit is always closed, so the impedance of the series coil of the measuring instrument and the protection circuit is very small, and the working state of the current transformer is close to a short circuit. The current transformer is used to convert the large current on the primary side into a small current on the secondary side, and the secondary side cannot be opened.

The role of the transformer:The transformer is a special transformer that uses the principle of electromagnetic induction to convert current and voltage. The transformer transmits the power information in the primary circuit to the secondary circuit in a certain proportion.

It is provided with secondary equipment such as measuring instruments and relay protection devices to monitor, measure and protect the system.

Due to the transformer's.

There is sufficient dielectric strength between the primary and secondary windings, which can make the secondary equipment and staff electrically isolated from the primary high voltage, and the secondary side of the transformer is grounded at a point to ensure the safety of equipment and personnel.

Transformer is divided into voltage transformers.

and current transformers.

1) The voltage transformer converts the high voltage into the low voltage, the rated voltage of the secondary winding.

100 V in parallel with the voltage coils in measuring instruments and protective relays.

2) The current transformer converts the large current into a small current, and the rated current of the secondary winding.

5A or 1A in series with current coils in measuring instruments and protective relays.

The function of the transformer is to reduce the AC voltage and high current to a value that can be measured directly by the instrument, which is convenient for the instrument to measure directly, and at the same time provides power for relay protection and automatic devices.

The transformer for power system is a special transformer that transmits the information of high voltage and high current of the power grid to the metering, measuring instrument and relay protection and automatic device of the secondary side of low voltage and small current, and is the connecting element of the primary system and the secondary system, and its primary winding is connected to the power grid, and the secondary winding is connected with the measuring instrument and protection device respectively.

The transformer works with measuring instruments and metering devices to measure the voltage, current and electrical energy of the primary system; In conjunction with relay protection and automatic devices, it can constitute electrical protection and automatic control of various faults in the power grid.

The performance of the transformer directly affects the accuracy of power system measurement and metering and the reliability of the operation of relay protection devices.

The instrument transformer is used to extend the measuring range of the instrument.

For example, the standard meter of the current transformer is 5A, and the transformer of 100 5 will expand the range of the 5A meter by 20 times, which is 100A

The voltage transformer, the standard voltmeter is 100V, after 10000 100 voltage transformer, the range is expanded by 100 times.

Secondly, for high currents or high voltages, it is not convenient to measure directly. It is dangerous for 10000V high voltage to enter the distribution cabinet directly. After the transformer becomes 100V, it is much safer.

The transformer can reduce the AC voltage and high current to a value that can be measured directly by the instrument, which is convenient for direct measurement by the instrument, and at the same time provides power for relay protection and automatic devices. Transformer is divided into two categories: voltage transformer and current transformer, and voltage transformer can be used for voltage and power measurement in high-voltage and ultra-high-voltage power systems.

According to your description, your meter is equipped with a transformer; Therefore, the power consumption is also multiplied by the multiplier of the transformer.

In the energy metering, if you need to convert a large current or large voltage into a small current or small voltage suitable for meter measurement, you need to use a "voltage transformer" and "current transformer" to convert according to a certain ratio, which is the comprehensive ratio.

We hope you find ours helpful.

There are two types of transformers, which are current transformers and voltage transformers.

The function of the current transformer is mainly to turn a large current into a small current.

The function of a voltage transformer is mainly to turn a high voltage into a low voltage.

Through current transformers and voltage transformers, we can know the changes of current and voltage in the power system, monitor the changes of various elements of the power system, monitor them at any time, and achieve the purpose of power system automation through the monitoring and control of various instruments and meters.

The transformer can play a role in detection.

Transformer includes voltage transformer and current transformer.

Voltage transformer is a kind of voltage conversion device, which has the dual functions of voltage conversion and isolation, which converts the high voltage of the high-voltage circuit or low-voltage circuit into low voltage (generally 100V), and supplies the instrument and relay protection device to achieve measurement, measurement, protection and other functions.

The current transformer is a kind of current conversion device, which has the dual functions of current conversion and isolation, which converts the large current of the high-voltage circuit or low-voltage circuit into a low-voltage small current (generally 5A), and supplies the instrument and relay protection device to achieve measurement, measurement, protection and other functions.

In order to better match the range of the instrument, there are also transformers that convert a small current below 5A into a large current (5A).

The transformer is divided into two categories: voltage transformer and current transformer, and its main functions are:

1. Accurately transmit the voltage and current information of the primary system to the relevant equipment on the secondary side.

2. The high voltage and high current of the primary system are converted into the low voltage and small current of the secondary side, so that the measurement, metering instruments and relays and other devices are standardized and miniaturized, and the insulation requirements for the secondary equipment are reduced.

3. The secondary side equipment and the secondary system are well isolated from the high-voltage equipment of the primary system in terms of electric gas distribution, so as to ensure the safety of the secondary equipment and personnel.

The transformer is divided into two categories: voltage transformer and current transformer, and its main functions are:

1. Accurately transmit the voltage and current information of the primary system to the related equipment on the secondary side.

2. The high voltage and high current of the primary system are converted into the low voltage and small current of the secondary side, so that the measurement, metering instruments and relays and other devices are standardized and miniaturized, and the insulation requirements for the secondary equipment are reduced.

3. The secondary side equipment and the secondary system are well isolated from the primary system in terms of high-voltage air modification, so as to ensure the safety of the secondary equipment and personnel.

Transformers: divided into voltage transformers, current transformers, zero sequence transformers, etc.

Voltage transformer: change different voltages into a unified value to match the meter or meter, and the secondary voltage is mostly 100V or 220V

Current transformer: change different currents to a unified current value to match the meter or meter, and the general secondary current is 5A

Zero sequence transformer: It mainly measures the neutral line current, and is a sensitive current transformer, which can measure tens of milliamperes of current for the second time.

Instrument transformer, also known as instrument transformer, is a general term for current transformer and voltage transformer. It can turn high voltage into low voltage and high current into small current for measurement or protection system. Its function is mainly to convert high voltage or high current into standard low voltage (100V) or standard low current (5A or 1A, both refer to rated values) in proportion, so as to realize the standardization and miniaturization of measuring instruments, protection equipment and automatic control equipment.

At the same time, the transformer can also be used to isolate the high-voltage system to ensure the safety of people and equipment.

Follow-up: I use a 10 (60A) meter to use 220W and want to use 40kw of electricity.

Transformer is divided into voltage transformer and current transformer.

The role of the current transformer.

When measuring the large current of alternating current, in order to facilitate the measurement of the secondary instrument, it needs to be converted into a relatively uniform current (China stipulates that the secondary rating of the current transformer is 5A, and the secondary rating of the current transformer in China is 5A), and the voltage on the line is relatively high, so it is very dangerous to measure directly. The current transformer plays the role of converter and electrical isolation, and the current transformer is the step-up (down-current) transformer. It is a sensor for secondary equipment such as measuring instruments and relay protection in the power system to obtain current information of the electrical primary circuit, the current transformer converts the high current into a low current in proportion, the current transformer is connected to the primary system on the primary side, and the secondary side is connected to the measuring instrument and relay protection.

There are only 1 to a few turns on the primary side, and the wire cross-sectional area is large, which is connected into the circuit under test. The secondary side has a large number of turns and a thin wire, which forms a closed circuit with a small impedance meter (the current coil of the ammeter power meter).

The operation of the current transformer is equivalent to the transformer with a short circuit on the secondary side, and a very low magnetic density is generally selected, and the excitation current is ignored, then i1 i2=n2 n1=k.

The current ratio of the primary winding current i1 to the secondary winding i2 of the current transformer is called the actual current ratio The excitation current is the main source of error. , 1 indicates that the ratio error is not more than 1%.

The role of the voltage transformer:

1. Provide the necessary signal for the reclosing, the way of reclosing on both sides of a line is either to detect no voltage, or to detect the same period, and the line PT can provide voltage signals for the reclosing.

2. At present, the capacitive voltage transformer used in PT of some lines can provide signal channels for carrier communication.

3. At present, the metering voltage is provided for some special power supply user lines.

4. Convert the high voltage of the system into a standard low voltage (100V) to provide the necessary voltage for the instrument and protection.

5. Cooperate with the measuring instrument to measure the phase voltage and line voltage of the line; Cooperate with relay protection devices to protect the system and equipment from overvoltage and single-phase grounding.

6、.Isolate primary equipment and secondary equipment to protect the safety of people and equipment.