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 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.
Jieli Electric officially moved its factory in June. The location was moved from Xiangyang Industrial Zone, Liushi Town, Yueqing City, to No. 81, Xiangbei East Road, Yishan Village, Liushi Town, Yueqing City.
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.
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.
What role do low voltage circuit breakers play?
How does a low voltage circuit breaker work?
What are the components and working methods of low voltage circuit breakers?
1.low voltage circuit breakers are mainly used in low voltage circuits to protect electrical equipment from short circuits, or if the voltage is abnormal or the current is too high, the circuit breaker can avoid some dangerous accidents.
2.The low voltage circuit breaker is very suitable for machine tools as it can take on a variety of protective functions. When the machine tool equipment is working, the low voltage circuit breaker is installed, so it does not need to be started frequently to avoid damage to the associated equipment.
3.There is an alarm contact in the low voltage circuit breaker. When the circuit is overloaded or a short circuit occurs, the alarm contact emits a sound, or a indicator light lights up to remind people in time to avoid major accidents.
The low voltage circuit breaker has great advantages over the knife switch when entering the house. First, it can interrupt a large current and has an arc extinguishing device, which is suitable for increasing the load of the house circuit. In addition, its thermal stability and service life are better than that of the knife switch. The second is that it can automatically interrupt the circuit if an error occurs. There are two triggers in the circuit breaker, one is a thermal bimetal trigger, which is used for overload delay protection; the other is an electromagnetic trigger used for immediate short circuit protection.
After using the circuit breaker, the fuse is no longer installed in the house circuit. When an error occurs, the trigger automatically triggers (commonly known as triggering) to interrupt the circuit. When the error is fixed, it can be reused simply by resealing without replacing parts.
The low voltage circuit breaker consists of three basic components: contact and arc extinguishing system, trigger, transmission and actuation mechanism. The contacts shown in the drawings are closed, and the latch locks this closed state with a hook to stabilize it. In case of overload, the overload trigger responds and the small multiple overload current bends the bimetal slightly after a certain time. The contacts are separated for overload time delay protection. When a short circuit occurs, the short circuit trigger acts, and the multiple short circuit current quickly attracts the anchor by the magnetic force generated by the electromagnet to move it downwards. stable, the contacts are quickly disconnected to achieve immediate short-circuit protection.
JIELI Electrical Engaged in research and development, production and supply chain management of MCB, RCCB and related supporting products.
low voltage circuit breakers are also called automatic air switches or automatic air circuit breakers. The low voltage circuit breakers sold on the market can not only be switched manually, but also equipped with automatic switching. If a short circuit occurs in the circuit or the current is too high, it can automatically interrupt the circuit and take on a protective function in time.
What is the main structure and function of the low voltage circuit breaker?
What are the main components of the low voltage circuit breaker?
What are the precautions for using low voltage circuit breakers?
1.Accessories for low voltage circuit breakers such as working current trigger, undervoltage trigger, electric drive, etc.; Shunt and undervoltage are voltage coils, as long as the voltage values are the same, they are used for AC systems, not AC systems. It can be used in DC systems without changes. Auxiliary, alarm contacts, AC and DC mass. The electric drive must be redesigned for DC operation.
2.Since the DC current does not have the zero-pass characteristics of alternating current, the interruption of DC short-circuit current (even the residual current with a small multiple); Erasing the arc is difficult, so the wiring should be connected two-pole or three-pole in series. increase the fracture so that each fracture carries part of the arc energy.
3.low voltage circuit breaker In addition to the traditional thermal magnetic trigger, the electronic trigger is also widely used. An important advantage of the electronic trigger is that it can operate stably even with changes in ambient temperature.
1. Contact
The contacts mechanically connected to the opening and closing mechanism of the main circuit of the low voltage circuit breaker are mainly used to indicate the opening and closing state of the circuit breaker, and are connected to the control circuit of the circuit breaker, to implement the opening and closing of the circuit breaker to the associated electrical appliances. Control or locking. For example, output signals on signal lamps, relays, etc.
2. Release
The working current trigger is a remote-controlled opening accessory. The under voltage trigger is used to automatically disconnect the low voltage circuit breaker to interrupt the power supply when a certain voltage drop in the power supply voltage occurs in the protected circuit, so that the electrical load equipment or electrical equipment below the circuit breaker is protected from under voltage damage.
3. Electric drive
It is an accessory for circuit breakers for automatic opening and closing over long distances. There are two types of electric drives: motor drive and electromagnetic drive.
Since direct current does not have zero-pass characteristics such as alternating current, it is difficult to interrupt the short-circuit current of direct current (even the residual current with a small multiple); It is difficult to extinguish the arc, so the wiring should apply the method of two-pole or three-pole series connection to increase the fracture, so that each fracture carries part of the arc energy.
In addition to the traditional thermal magnetic trigger, the electronic trigger is also widely used. An important advantage of the electronic trigger is that it can operate stably even with changes in ambient temperature.
JIELI Electrical has been active in the low voltage circuit breaker industry for almost twenty years. Dedicated to research and development, production and supply chain management of MCB, RCCB and related supporting products.
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.
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.
