low voltage circuit breakers are widely used in low voltage power distribution systems at all levels, to control the power of various mechanical devices, and to control and protect power connections.
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.
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.
A low voltage circuit breaker is a switching device that can not only turn normal load current and overload current on and off, but also can turn short circuit current on and off. In addition to the control function in the circuit, the low voltage circuit breaker also has a certain protective function.
What is the protective function of the low voltage circuit breaker?
What is the plug wiring for low voltage circuit breakers?
What is the key structure of the low voltage circuit breaker?
Protection functions of low voltage circuit breakers: short circuit protection, overload protection and undervoltage protection.
low voltage circuit breakers were formerly referred to as automatic switches or air switches. In addition to full load shutdown capability, it also has functions such as short circuit protection, overload protection and undervoltage protection, and has good arc extinguishing ability. It is often used as a main switch or secondary circuit switch in the distribution box. low voltage circuit breakers should not be operated frequently and are suitable as control units in lighting distribution boxes or other rare operations.
On the mounting plate of the complete set, first install a circuit breaker mounting seat, on the mounting seat there are 6 connectors, and on the connecting plate of the circuit breaker there are 6 sockets. There is a connecting plate on the surface of the mounting seat or bolt behind the mounting seat, and the power line and load line are pre-connected to the mounting seat. Insert the circuit breaker directly into the bracket for use. If the low voltage circuit breaker is defective, just pull out the bad one and replace it with a good one. Its replacement time is shorter and more convenient than the wiring before and after the board. Because plugging in and out requires a certain amount of manpower. This saves maintenance and replacement time. When installing a pluggable circuit breaker, check that the circuit breaker plug is firmly depressed and securely fasten the circuit breaker to reduce contact resistance and improve reliability.
1. Energy-releasing electromagnet
When the user presses the button after the electromagnet coil is excited, the electromagnet is closed to release the energy storage spring, and the circuit breaker is closed.
2. Turn the handle
The operator rotates the handle outside the door clockwise or counterclockwise to ensure the circuit breaker closes or opens. At the same time, turning the handle can ensure that the cabinet door cannot be opened when the circuit breaker is closed; only when the handle is opened or buckled, the door of the control cabinet can be opened. In an emergency, when the circuit breaker is "on" and the door needs to be opened, the red release button can be pressed on the side of the rotary handle base.
JIELI Electrical has three production sites all over the world, namely in Poyang, Jiangxi, China, Yueqing, Zhejiang, China, and Yangon, Myanmar. Own an annual production capacity of 20 million PCS for MCB and 1 million PCS for RCCB. Our clients are located in almost 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.
The 132th China Import and Export Fair (Canton Fair for short) will be held online from October 15th to 24th and will last for 10 days. 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 breakers are characterized by small size, simple structure and convenient operation. The contact material of the DC miniature circuit breaker is made of copper-based alloy and has been specially treated to reduce the contact resistance and reduce the temperature coefficient.
1.The upper limit of ambient air temperature must not exceed +40℃, the lower limit must not be lower than -5℃, and the average temperature value of 24 hours must not exceed +35℃;
Note 1: If the lower limit is -10 °C or -25 °C, the user must inform the manufacturer when ordering;
Note 2: If the upper limit exceeds +40℃ or the lower limit is below -25℃, the user should negotiate with the manufacturer.
2. The height of the site must not exceed 2000 m;
3. The relative humidity of the atmosphere does not exceed 50% if the ambient air temperature is +40 °C, and at lower temperatures a higher relative humidity is allowed, e.g. 90% at +20 °C. condensation should take appropriate measures;
4. degree of pollution: 2;
5. Installation category: Class II and Class III;
6.The external magnetic field of the installation site should not exceed 5x the earth's magnetic field in any direction;
7. Generally installed vertically, with a tolerance of 2° in each direction;
8.There should be no significant vibration or vibration at the installation site.
The miniature circuit breaker is characterized by advanced structure, reliable performance, strong switching power, beautiful appearance and compact appearance. It is mainly used in places with alternating current 50 Hz or 60 Hz, rated voltage below 400 V and rated operating current below 63 A. It is used for overload and short circuit protection of lighting, distribution lines and equipment in office buildings, residential buildings and similar buildings, and can also be used for the rare on-off operation and conversion of lines. Miniature circuit breakers are mainly used in various places such as industrial, commercial, high-rise and residential buildings.
1. Breakable contact connection. It consists of fixed contacts and movable contacts.
2. Equipment consisting of metal cylinders or insulating cylinders incorporating separable contact connections and arc extinguishing devices and transmissions.
3. The transmission device that drives the contact.
4. Arc extinguishing equipment.
When the miniature circuit breaker breaks the circuit, it uses a mechanical method to separate the moving contact and the fixed contact of the miniature circuit breaker. When closing, the movable contact and the fixed contact are closed by the opposite mechanical movement. During the closing and breaking of the load circuit, an arc is generated between the fixed contact and the movable contact. The arc generated during the opening process is much stronger than during the closing process. If the cut-off current is very large, especially when breaking a short circuit, the arc is very large, and it is often very difficult to disconnect the circuit.
JIELI Electrical maintains close relationships with customers in miniature circuit breaker industry, and is committed to strengthening p
roduction and operation, improving quality and safety.
The miniature circuit breaker is the most widely used terminal protection device in the construction of electrical terminals for power distribution. It is used for single-phase and three-phase short circuit, overload and overvoltage protection under 125 A, including single-pole 1P, two-pole 2P, three-pole 3P and four-pole 4P.
The typical size of the miniature circuit breaker is 18 mm width as module (1 bit, 1 P) and 9 mm as module. Friends should pay attention to their statement when buying to prevent the sizing of the distribution box top. Mistakes. In fact, 9 and 18 can be converted if we use it. Micro-Break has two frame currents 63A and 125A. The 1st position of the microfracture below 63 A is 18 mm, and the 1st position of the 125-frame current is 27 mm.
When a miniature circuit breaker in the distribution box needs to be replaced, it is accidentally jammed in the middle. We can only remove the wire and pull the clip on the bottom of the miniature circuit breaker to separate it from the guide rail. The clip is uncomfortable to pull by hand. Without a slotted screwdriver, it is not easy to lever.
Compact circuit breakers have a current carrying capacity of up to 2000 A. The maximum rated current of miniature circuit breakers is within 125 A.
Due to the capacity difference between the two, in the specific work, the effective area of the Compact circuit breaker is also larger than that of the miniature circuit breaker, and the wires connected to it are also relatively thick, which can reach more than 35 square meters, while the miniature circuit breaker is only suitable for connecting 10-wire below the square. Therefore, in general, for indoor conditions, it is better to choose compact circuit breakers for larger rooms.
When selecting a miniature circuit breaker, the following conditions should be considered:
1) The rated voltage of the miniature circuit breaker should not be less than the rated voltage of the line;
2) The rated current of the miniature circuit breaker and the rated current of the overcurrent trigger are not less than the calculated current of the line;
3) The rated short-circuit switching capacity of the miniature circuit breaker is not less than the maximum short-circuit current in the line;
4) The selection of miniature circuit breakers for power distribution shall take into account the short-term delayed short-circuit on-off capability and the coordination between the delay protection levels;
5) The rated voltage of the miniature circuit breaker's undervoltage trigger is equal to the rated voltage of the line.
JIELI Electrical has been active in the low voltage miniature circuit breaker industry for almost twenty years. Dedicated to research and development, production and supply chain management of MCB, RCCB and related supporting products. It is not only 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.