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What role do low voltage circuit breakers play?
What are the relevant parameters of low voltage circuit breakers?
What types of low voltage circuit breakers are there?
low voltage circuit breakers refer to mechanical switching electrical appliances that can connect, charge and disconnect current under normal circuit conditions and can be connected, charged and disconnected for a specified period of time under certain abnormal circuit conditions. Perform switching operations on power distribution circuits, motors or other electrical equipment to perform a protective function according to the specified conditions. In other words, it is a switch that can automatically interrupt the circuit if overload, short circuit or undervoltage occurs during the flickering of the circuit.
low voltage circuit breakers are used to distribute current, prevent the frequent operation of asynchronous motors, power lines and motors, etc. protect and automatically shut off circuits in case of major overloads, short circuits, undervoltages and other errors and combine fuse load switches and overheating relays. In addition, no parts need to be replaced after the residual current is interrupted. It's widespread now.
1.The model of low voltage circuit breaker is generally composed of text symbols and numbers according to the national technical standards as follows:
2.The letter number of the product is represented by the following letters. s%)fewer oil switches; d. circuit breakers for more oil k. circuit breakers for air L. circuit breakers for sulfur hexafluoride; Z. Vacuum circuit breakers; Q. Gas generator circuit breaker; C. Arc deflection circuit breaker.
3. Installation location code; n---inside, w---outside.
4. serial number of the design series; represented by points 1, 2, 3.
5. Rated voltage, KV.
6.Other supplementary work characteristics identification, G-enhanced, F-phase separated operation.
7. Rated current, A.
8. Rated switching current, KA.
9. Special environment code. Fingers empty like DZ47-63. DZ47LE-63 with leakage. C16: refers to the current of 16A. Residents of normal households use C10-16, and the construction uses C32 or higher.
1) (Mechanical) circuit breaker
A mechanical switchgear capable of generating, conducting and interrupting current under normal circuit conditions and capable of generating, conducting, conducting and interrupting current even under certain abnormal circuit conditions (e.g., short circuit). Formerly known as: Automatic Switch
2) Universal circuit breaker
A circuit breaker that integrates all components with a frame structure base with insulating pads and has various structural changes and uses.
Formerly known as: Frame Type Automatic Switch
3) circuit breaker with plastic housing
A circuit breaker with a housing made of molded insulating material and all components assembled in one. Synonym: compact circuit breakers
Formerly known as: Automatic switch with plastic housing
JIELI Electrical not only has a production service provider solving supply chain problems, but also a manufacturer offering OEM and ODM production services.
There are many classification methods for low voltage circuit breakers. Depending on the type of use, a distinction is made between selective and non-selective species. Depending on the arc extinguishing medium, there are air type and vacuum type. low voltage circuit breakers have a wide range of capacities with a minimum of 4 A and a maximum of 5000 A.
What is the function of the low voltage circuit breaker?
What are the operating steps of a low voltage circuit breaker?
How does the overload protection of the low voltage circuit breaker work?
A low voltage circuit breaker, commonly known as automatic air switch, is a low voltage electrical device that can automatically interrupt a faulty circuit and has both control and protection functions. In low voltage circuits, it is used to interrupt and connect load circuits to control the operation and stopping of motors. If the circuit is overloaded, short-circuited, voltage loss and other faults, it can automatically turn off the faulty circuit to protect the safety of the circuit and electrical equipment. Its protective effect parameters can
be artificially adapted to the requirements of electrical equipment, and it is convenient and reliable to use. It is worth noting that after disconnecting the contact of the low voltage circuit breaker, the actuation handle is still in the "closed" position, and the handle must be moved to the "open" position, and then to the "closed" position. Position.
The operation of the low voltage universal circuit breaker is divided into electrical and manual operation.
Electric operation, first press energy storage button, after inserting the energy storage press close button. If there is no stored energy, press the close button directly. Manual operation, use the special control handle on the universal circuit breaker to manually store the energy up and down on the universal circuit breaker, and press the power button on the circuit breaker after the indicator is attached.
The low voltage circuit breaker uses time delay protection for long-term overload protection. When a thermally actuated (bimetal element) is used for long-term overload protection, its action source is i2r, and the effective value of AC is equal to the average value of DC, so no change is required. However, if the secondary current heating of the current transformer is adopted for high current specifications, the transformer cannot be used in the DC circuit and cannot be used.
If the long-delay overload trigger of low voltage circuit breaker is completely electromagnetic (hydraulic type, namely oil cup type), the time delay trigger characteristics should change, and the minimum operating current should be increased by 110% to 140% . Therefore, the fully electromagnetic AC trigger unit cannot be used in the DC circuit (if used, it must be redesigned).
JIELI Electrical has the production base that has passed the international certification of ISO9000 quality system. Zhejiang's production base is still a local patent demonstration enterprise and high-tech enterprise.
The miniature circuit breaker is also a circuit breaker product with a wide selection and quantity, and its main function is to protect the electrical junction distributor device of the building. It is suitable for overload and short circuit protection of AC 50/60 Hz, rated voltage 230/400 V, rated current up to 63 A, and also can be used for the rare operation and conversion of lines under normal conditions, mainly for industry, commerce, high rise and residential buildings and other places.
The miniature circuit breakers consist of drives, contacts, protective devices (various triggers) and arc extinguishing systems. Its main contacts are manually operated or electrically closed. After closing the main contact, the release mechanism locks the main contact in the closed position. The coil of the overcurrent trigger and the thermocouple of the thermal trigger are connected in series with the main circuit, and the coil of the undervoltage trigger is connected in parallel with the power supply. In case of short circuit or strong overload of the circuit, the anchor of the overcurrent trigger is tightened to release the free trigger, and the main contact disconnects the main circuit. When the circuit is overloaded, the thermocouple of the thermal trigger heats up and bends the bimetal, thereby activating the free release mechanism. In case of undervoltage in the circuit, the anchor of the undervoltage trigger falls off.
1) The installation of the miniature circuit breaker should meet the requirements of GB13955-92 standard and product manual.
2) When installing the miniature circuit breaker, the power supply line, power supply mode, power supply voltage, and grounding type of the system should be fully considered.
3) The rated voltage, rated current, short-circuit shutdown capacity and shut-off time of the miniature circuit breaker shall meet the requirements of the protected power supply line and electrical equipment.
4) The installation and wiring of the miniature circuit breaker should be correct. Special attention should be paid to the wiring of the residual current miniature circuit breaker in single-phase, three-phase three-wire and three-phase four-wire power supply systems of different grid grounding forms.
(1) The arc extinguishing chamber is formed into a polygon;
(2) coating a layer of conductive carbon film on the inner wall of the arc extinguishing chamber;
(3) use graphite as an arc extinguishing agent;
(4) Increase the number of auxiliary contacts, etc.
JIELI Electrical is not only a production service provider solving supply chain problems, but also a manufacturer offering OEM and ODM production services. Do you need help with low voltage miniature circuit breakers? Fill out this form to contact us. JIELI Electrical has been active in the low voltage miniature circuit breaker industry for almost twenty years.
At the regular press conference held by the Ministry of Commerce on September 10, the spokesperson Gao Feng introduced that the 128th China Import and Export Fair (Canton Fair for short) will be held online from October 15th to 24th and will last for 10 days. Gao Feng said that continuing to hold the Canton Fair online will help further play the role of the Canton Fair's all-round opening up platform, promote the stable and healthy development of foreign trade under normal epidemic prevention and control, and facilitate the smooth flow of the foreign trade industry chain and supply chain. We will work hard to provide better and more convenient services for exhibitors and merchants. Welcome Chinese and foreign enterprises and businessmen to actively participate in the exhibition and negotiate purchases.
The miniature circuit breaker is mainly used for home use and generally only has short-circuit and overload protection. However, it is small in size, low in price, and easy to maintain. It is generally used at home. The maximum cutting capacity does not exceed 10KA.
MCB is a miniature circuit breaker, while RCB is a circuit breaker with residual current protection. Different loads should use different types of circuit breakers.
An MCB or miniature circuit breaker is an electromagnetic device that embodies a complete enclosure in a molded insulating material. The main function of the MCB is to switch the circuit, i.e. automatically turn on the circuit (already connected to it) when the current through it (MCB) exceeds the value it is set to. It can be turned on and off manually like a normal switch if needed.
If it is a C40 type circuit breaker, it is generally suitable for use in home power distribution and lighting circuits, such as for controlling power distribution or lighting connections. If it is a D63 type circuit breaker, it is used to control industrial motors.
If it is a C40 type circuit breaker, its sectional capacity is about 4 to 7 times, while the sectional capacity of a D-type circuit breaker is slightly higher, which can reach between 7 times and 10 times.
The tripping current of the C40 type circuit breaker is 5-10 times the rated current, and the tripping current of the D63 type circuit breaker is 10-14 times the rated current.
Traditional AC miniature circuit breakers are mainly used as short-circuit or over-current protection appliances in power systems with AC 50hz and above. Due to the increasing requirements for power grid security and the rapid development of computer technology in recent years, people have begun to study new intelligent low-voltage switchgear to replace traditional low-voltage circuit breaker products. Among them, intelligent high-voltage vacuum load switch is characterized by its unique function which has been widely used.
With the continuous improvement of industrial automation and the increasing emphasis on environmental protection, people have put forward higher requirements for the reliability and service life of electrical equipment. Therefore, there are many new intelligent components such as miniature circuit breakers and leakage protectors in the intelligent low-voltage power distribution cabinets currently on the market.
JIELI Electrical has three production bases around the world, namely in Poyang, Jiangxi, China, Yueqing, Zhejiang, China, and Yangon, Myanmar. The production base has passed the international ISO9000 quality system certification. Zhejiang's production base is still a local patent demonstration enterprise and high-tech enterprise. Possess an annual production capacity of 20 million PCS for MCB and 1 million PCS for RCCB. The customers served are in nearly 50 countries around the world.
The main components of the low voltage circuit breaker are: contacts, triggers, electrical actuators, energy release electromagnets, rotatable actuation handles, extended handles, handle locks, etc.
Which common low voltage circuit breakers do you know?
How to choose a suitable low voltage circuit breaker?
Why do we need to understand low voltage circuit breakers?
Which common low voltage circuit breakers do you know?
1) Current limit switch
A circuit breaker whose shutdown time is short enough to interrupt before the short-circuit current reaches its expected peak value.
2) Plug-in circuit breaker
A circuit breaker equipped with a plug contact (or contact seat) on the terminal to insert the corresponding static contact seat (or contact) and connect it to the external wire.
3) Circuit breakers for removal
It's some kind of pluggable circuit breaker. There is a special circuit breaker support mechanism during plug-in, which can support the circuit breaker even when the inserted contacts are in the separate position, ensuring a safe isolation distance. Drawer circuit breakers should generally have three positions: connect, test and disconnect.
4) Circuit breaker with fuse
A single electrical device consisting of a circuit breaker and a fuse, each phase being formed in series by a fuse and a pole of the circuit breaker.
5) With self-retaining circuit breaker against switching on
A circuit breaker in which the movable contacts do not conduct current, even if a command to close is given, if the conditions that caused the opening process persist.
6) Open circuit breaker
A circuit breaker that opens and closes in the open air
There are also many models of low voltage circuit breakers on the market. For example, there are dz47, which are small circuit breakers, and z20, including dw15 and so on. Different models have different applications.
When choosing, we should decide according to the current load capacity in the circuit, which type of circuit breaker to choose. You must not choose the wrong one, otherwise the circuit breaker will not play a protective role, but it will pose certain safety risks to our power consumption.
When it comes to the technical parameters of low voltage circuit breakers, most electrical professionals need to be very clear, but when it comes to the importance of the parameters of low voltage circuit breakers, many electrical professionals can be confused. low voltage circuit breakers are an important component of low voltage electrical products in the energy industry. With the further improvement of the degree of automation, the performance and service life requirements of circuit breakers are getting higher and higher, and the reliability of circuit breakers is mainly determined by their actuation mechanism. Reliability. Therefore, it is of great importance and practical value to investigate the reliability and optimal design technology of the low voltage circuit breaker drive.
JIELI Electrical has been active in the low voltage circuit breaker industry for almost twenty years. JIELI Electrical Engaged in research and development, production and supply chain management of MCB, RCCB and related supporting products.
At the regular press conference held by the Ministry of Commerce on September 10, the spokesperson Gao Feng introduced that the 128th China Import and Export Fair (Canton Fair for short) will be held online from October 15th to 24th and will last for 10 days. Gao Feng said that continuing to hold the Canton Fair online will help further play the role of the Canton Fair's all-round opening up platform, promote the stable and healthy development of foreign trade under normal epidemic prevention and control, and facilitate the smooth flow of the foreign trade industry chain and supply chain. We will work hard to provide better and more convenient services for exhibitors and merchants. Welcome Chinese and foreign enterprises and businessmen to actively participate in the exhibition and negotiate purchases.
There are many classification methods for low voltage circuit breakers. Depending on the type of use, there is a selective type (protective device parameters are adjustable) and a non-selective type (protective device parameters are not adjustable). Depending on the arc extinguishing medium, there are air type and vacuum type.
What is the use value of low voltage circuit breakers?
What parameters should be considered when selecting a low voltage circuit breaker?
What is a low voltage circuit breaker?
low voltage circuit breakers are electrical devices used for switching, controlling or protecting circuits with AC voltage of 1200 V and DC voltage of 1500 V. low voltage circuit breakers are an important part of the electrical industry and basic accessories in the machinery industry. In the power distribution system, low voltage switchgear mainly consists of various low voltage circuit breaker components. The functions and performances of low voltage circuit breakers play a crucial role. More than 80% of the electrical energy generated by power generation plants is distributed and used via low voltage circuit breakers. For each additional 10,000-kW power generation system, approximately 20,000 pieces of different low voltage circuit breakers are required to adjust them. Industrial automation systems also require various control panels, consoles, controllers and other products consisting of low voltage circuit breakers.
1) Type:
The type of circuit breaker includes the number of phases, the number of poles, the rated frequency, the arc extinguishing medium, the closing method and the shutdown method.
2) Rated power of the main circuit:
Main circuit ratings are:
rated operating voltage; rated current; rated short-term switching capacity; Design short-term current resistance.
The rated current of the universal circuit breaker is also divided into the rated current of the main circuit and the rated current of the frame plane.
3) Work system assessed:
The rated load system of low voltage circuit breakers can be divided into two types: 8-hour system and long-term system.
4) Subcircuit parameters:
The auxiliary circuit parameters of low voltage circuit breakers are mainly the characteristic parameters of auxiliary contacts. Universal circuit breakers usually have 3 pair closers and 3 pair openers for signal devices and control circuits; Compact circuit breakers usually have no auxiliary contacts.
low voltage circuit breakers are also called automatic air switches or automatic air circuit breakers or short circuit breakers. It is an electrical device that has both manual switching functions and automatic power failure, undervoltage, overload and short circuit protection. It can be used to distribute electrical energy, rarely start asynchronous motors, protect power supply lines and motors, etc. Its function corresponds to a fuse switch and overheating relay and other combinations. In addition, it is generally not necessary to replace parts after the residual current is interrupted, and it is widely used.
JIELI Electrical Engaged in research and development, production and supply chain management of MCB, RCCB and related supporting products.