Oil circuit breaker electric arc insulator electricity. Most of the newer industrial circuit breakers are now using sf6 gas to extinguish the arc as a response to concerns for the environment and the costs involved in oil spills that can happen with the oil type circuit breakers. Oilcircuit breaker vacuum circuit breaker sf6 circuit breaker bulk oil circuit breaker air cushion low oil circuit breaker consists of two parts. In this article, the different types of circuit breakers, i. Oil circuit breaker minimum oil circuit breakers latest. The are control device is fitted to the upper to the upper fixed contact. The quantity of oil requires in bulk oil circuit breaker depends on the system voltage. Ppt circuit breaker powerpoint presentation free to. Felix delivers trouble free operation with m2 class compliance. In a minimum oil circuit breaker, the interrupter is enclosed in an oil filled chamber at live. The new vcb uses either the existing secondary isolating contacts or a new higher integrity plug and socket. Oil circuit breaker synonyms, oil circuit breaker pronunciation, oil circuit breaker translation, english dictionary definition of oil circuit breaker. Its basic function is to interrupt current flow after a fault is detected. Bulk oil circuit breaker or bocb is such types of circuit breakers where oil is used as arc quenching media as well as insulating media between current carrying contacts and earthed parts of the breaker.
Circuit breaking chamber consist of fixed and moving contact 11 disadvantages of oil circuit breaker. Hv circuit breakers cb in transmission systems, if. Due to absence of oil in airblast circuit breaker, risk of fire and maintenance of oil is eliminated. Different types of circuit breakers and its applications elprocus. Bulk oil circuit breaker bulk oil circuit breaker or bocb is such types of circuit breakers where oil is used as arc quenching media as well as insulating media between current carrying contacts and earthed parts of the breaker. Pdf performance of bulk oil circuit breaker bocb influenced by. Figure 7 one pole of an extra high voltage air blast circuit breaker.
It insu lates between the phases and between the phases and the ground, and it provides the medium for the extin guishing of the arc. A systematic approach to highvoltage circuit breaker. The concept operation of the oil circuit breaker is simple compared to the. Circuit breaker operational health assessment via condition monitoring data. In the bulk oil circuit breakers discussed so far, the oil has to perform two functions. Pdf circuit breaker operational health assessment via. In oil circuit breaker the fixed contact and moving contact are immerged inside the insulating oil. Bulk oil circuit breakers, once the mainstay of distribution system short. Branch form fae 3214 11kv vacuum cb truck retrofits for bulk oil cbs product. Oil circuit breakers breaker service substation spare.
Retrofitting solutions for brush bulkoil vsi type circuit. Power transformers, oil filled reactors, large regulators, and circuit breakers are the greatest potential source of major oil spills in substations, since they typically contain the largest quantity of oil. Deterioration of oil is eliminated and the arcing products produced are completely removed. Firstly, it acts as an arc extinguishing medium and secondly, it insulates the live parts of the breaker from earth. Such type of circuit breaker is also known as dead tanktype circuit breaker because their tank is held at ground potential. In oil circuit breaker the fixed contact and moving contact are immerged. There is no special system for arc control other than the increase in length caused by the separation of contacts.
Elden in 1898 installed at the boston electric light company l street plant. The gas formed by the arc causes high pressure inside the arc control device. It can be understood that, the high affinity of absorbing free electron. Application, advantages and disadvantages of all types of. Oil circuit breaker in hindicb, circuit breakers in hindi,electrical in hindi.
Also, the preferred technology is dependent on the geographical region in which it is applied. So, it is called as an arc extinction chamber or current interruption chamber of minimum oil circuit breaker mocb. Bulk oil circuit breaker construction of bulk oil circuit breaker. While vacuum breakers are mainly used for voltage upto 38 kv, sf 6 breakers are used starting from distribution voltage at 11 kv upto 765 kv and 1200 kv level. Electrical test equipment application solutions from megger. Typically maintenance frequencies for the new circuit rps retrofit breakers are three times longer than those for the old oil circuit breakers. Mineral oil has better insulating property than air. The circuit breaker which uses more oil or which is bulky is called bulk oil circuit breaker. The product comes with compartmentalized construction and uses non hygroscopic epoxy mould for a long life. Since oil pressure developed is independent of the fault current to be interrupted, the performance at low currents is more consistent than with selfblast oil circuit breakers.
Oil circuit breaker bulk and minimum oil circuit breaker electrical4u. The main components of an oil circuit breaker and how does. The quantity of oil requires for arc extinction is only about onetenth of the. Oil circuit breaker ocb working principle, construction. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset either manually or automatically to resume. Oct 01, 2017 on the other hand, low oil circuit breaker only uses less oil compared to the bulk oil circuit breaker 4.
Air blast circuit breakers abcbconstruction,working. Actuator lever used to manually trip and reset the circuit breaker. The limits to exploitation of the oil for the bulk oil circuit breaker. It is suitable for both automatic operation and manual. This type of operation makes the breaker more reliable by removing any coating developed between sliding surfaces. Bulk oil circuit breakers are primarily used in north america in hv. I hope ki ye video dekhne ke bad apko pata lag jayega ki oil circuit breaker kya hai, inka working principle kya hai, construction kaisa or or maintenance kaise hota hai. Safe operation and maintenance of circuit breakers and switchgear. The basic construction of bulk oil circuit breaker is quite simple. Fast operation is possible and suitable for indoor installation. Rated short circuit breaking current 40 ka rated shorttime current up to 3 s 40 ka leakage rate per year circuit breaker spring rated operating sequence oco15sco interrupter technology vacuum insulation medium clean air bay width common pole drive 34 bay height, depth typical 106 x 18 bay weight. Oilfilled equipment in substation ieee 9801994 r2001.
Operating principle of minimum oil circuit breaker whenever the moving contact is drawn out of the. And their subdivision is also discussed along with advantages and disadvantages. The are extinction process is carried out in the upper chamber. The methods used to extinguish the arc include air blast, bulk oil, minimum oil, a vacuum and the sf6 sulfur hexafluoride gas.
Sep 15, 2017 i hope ki ye video dekhne ke bad apko pata lag jayega ki oil circuit breaker kya hai, inka working principle kya hai, construction kaisa or or maintenance kaise hota hai. Application these breakers are used up to 11 kv with. This chamber houses an arc control device, an upper fixed contact and a ring shaped lower fixed contact. Also the operating mechanism can be easily disassembled, checked and reassembled 2 answer of question no. In oil circuit breaker fixed contact and moving contact are immerged inside the insulating oil whenever there is a separation of current carrying contacts in the oil, the arc in circuit breaker is initialized at the moment of separation of contacts, and due to this arc the oil is vaporized and. These models can represent the probability of failures and how the failures are developed during the lifetime of hv circuit breakers. Application, advantages and disadvantages of oil, minimum oil, air blast, sulfur hexafluoride, vacuum circuit breaker. A circuit breaker is a protective device which can break the circuit automatically under the fault condition. Pdf performance examination of the bulk oil circuit breaker that is. Bulk oil circuit breaker or bocb is such types of circuit breakers where oil. These types of circuit breakers are of the livetank design and require only a small amount of oil. For bulk oil circuit breaker, we should check contact burning. Circuit breaker technology varies depending on the application.
To improve breaker performance, oil is injected into the arc. Power transformers, reactors, and regulators may contain anywhere from a few hundred to 100,000 l or more of oil 500 to approximately. The legendary cg make bulk oil circuit breaker bocb was a highly reliable product with world wide installations. It is pneumatically trip free on automatic operation and mechanically trip free on hand closing. Elden in 1898 installed at the boston electric light company l street plant later boston edison open tank with upward motion operation. Performance of bulk oil circuit breaker aip publishing. Bulk oil circuit breakers often use oil or resinimpregnatedpaper capacitivegraded bushings that are equipped with tap electrodes and have cts mounted on the lower ground sleeve. Oil circuit breaker diagram types of oil circuit breaker. In cross blast interrupters, the arc is drawn in front of several lateral vents. However, unlike bulk oil circuit breaker, a minimum oil circuit breaker places the interrupting unit in insulating chamber at live potential. Oil circuit breaker free download as powerpoint presentation.
Apr, 2017 this necessitates periodic checking and replacement of oil. It consists of current carrying contacts enclosed in a strong, weathertight earth metal tank and the tank is filled with transformer oil. Figure 4a 66 kv oil circuit breaker figure 4b bulk oil. The disconnecting circuit breaker dcb was introduced in 2000 and is a highvoltage circuit breaker modeled after the sf 6 breaker. Oil circuit breaker ocb working principle, construction and. The features of designing mocb are to reduce requirement of oil, and hence these breaker are called minimum oil circuit breaker. Also indicates the status of the circuit breaker on or offtripped.
B low oil circuit breakers types of oil circuit breakers 9. Oil circuit breakers types, working and construction. The following suggestions are for use in conjunction with the manufacturers instruction books for the maintenance of mediumvoltage oil circuit breakers. The oil is both acts as an arc extinguishing medium and as an insulator between the live part and earth. It presents a technical solution where the disconnecting function is integrated in the breaking chamber, eliminating the need for separate disconnectors.
Circuit breaker electric arc electromagnetism free 30. Oil circuit breaker bulk oil circuit breakers plain break oil c. Oil circuit breaker in hindicb,circuit breakers in hindi. Oil minimum circuit breakers are used in the ussr, the federal republic of germany, and france. Most of the newer industrial circuit breakers are now using sf6 gas to extinguish the arc as a response to concerns for the environment and the costs involved in oil spills that can happen with the oil type circuit. The gas inside the bubble is around 80% hydrogen, which impair s ionization. The main components of an oil circuit breaker and how does it. The quantity of oil required is reduced considerably. Sep 22, 2017 oil circuit breaker in hindicb, circuit breakers in hindi,electrical in hindi.
However, unlike bulk oil circuit breakers, these designs place the interrupting units in insulating chambers at live potential. For higher voltages and breaking currents, each pole is located in a separate tank. The use of the wellproven vd4 type circuit breaker allows the performances available with the abb switchgear to be extended, even for products made by other manufacturers. Oil circuit breakers electric arc series and parallel. Oil circuit breaker article about oil circuit breaker by. Minimum oil circuit breakers mocbcontruction,working.
You can also choose from 1, 3, and 2 oil circuit breaker, as well as from magnetic, high voltage, and vacuum oil circuit breaker, and whether oil circuit breaker is three, or single. Fundamentals of hv circuit breakers applications, failure. The insulating oil is available only in interrupting chamber. When electric arc is drawn under oil, the arc vaporizes the oil and creates a large bubble that surrounds the arc. It is pneumatically tripfree on automatic operation and mechanically tripfree on hand closing. Aug 15, 2015 bulk oil circuit breaker bulk oil circuit breaker or bocb is such types of circuit breakers where oil is used as arc quenching media as well as insulating media between current carrying contacts and earthed parts of the breaker. The construction is simple and it consists of fixed and moving contacts enclosed in a strong weather tight earthed tank containing oil up to a certain level and an air cushion above the oil level. These types of circuit breakers utilize oil as the interrupting media. Performance examination of the bulk oil circuit breaker that is influenced by its. Retrofitting replaces the oil circuit breaker with long life, low maintenance unit.
Moisture in oil astm d1533 microscopy dielectric breakdown astm d1816 other interfacial tension astm d971. A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit. The features of designing mocb is to reduce requirement of oil, and hence these breaker are called minimum oil circuit breaker. Different types of circuit breakers and its applications.
As the contacts are present in the dielectric oil, the oil surrounding the arc attains a high temperature and thus decomposes the releasing gases. Case in point, dead tank sf6 filled circuit breakers and bulk oil circuit breakers are primarily used in north america in hv applications, while the rest of the world. The oil is utilized primarily as the interrupting media, unlike in a bulk oil circuit breaker where the oil is utilised as an insulating media as well. For voltages of 10 kv or less and breaking currents of 15 ka or less, all three poles of the oil circuit breaker are located in the same tank. Check the condition, alignment, and adjustment of the contacts. Pcb bulk product waste includes, but is not limited to. The circuit breaker should be operated electrically from local and remote then mechanically from local. Vacuum breakers need virtually no maintenance and by comparison the time to check periodically the condition of a vacuum circuit breaker is negligible with no replacement parts required for many years. The usual application for this mechanism is for highspeed reclosing duty, but it is some. In bulk oil circuit breaker, oil performs mainly two functions. Since in large gas pressure, the mean free paths of electrons and ions are.
Circuit breaking chamber consist of fixed and moving contact disadvantages of oil circuit breaker it is inflammable and there is a risk of fire. The oil used here is same as transformer insulating oil. In its normal free state the arc loses energy by conduction, convection and radiation and. In many of the countries, the air circuit breaker is replaced by an oil circuit breaker. Medium volt circuit breakers work for volts that range from 1 to 72kv. Whenever there is a separation of current carrying contacts in the oil, the arc is initialized at the moment of separation of contacts, and due to this arc the oil is vaporized and decomposed in. The use of the wellproven vd4 type circuit breaker allows the performances available with the abb switchgear to be extended, even. Control circuit and contacts, verify trip, close, tripfreedwelltime, and. Everything you wanted to know about ac highvoltage circuit breakers but were afraid to ask ieee switchgear committee portland maine, usa, october 2017. Boa breaker oil analysis oil circuit breaker sample data. Each of those tanks has about 2500 gallons of mineral oil. A plainbreak oil circuit breaker is a bulk oil circuit breaker which involves the simple process of separating the contacts under the whole of the oil in the tank. Abb vacuum retrofitting circuit breakers allow the bulk oil based apparatus to be removed, thereby eliminating the fire hazard. Pdf types of circuit breaker and its application in.
Aug 09, 2018 the circuit breaker should be operated electrically from local and remote then mechanically from local. The circuit breaker can make or break the circuit either manually or by remote control. In modern power systems these two types of circuit breakers are mainly used for high voltage application. A wide variety of oil circuit breaker options are available to you, such as power, electronic. An oil circuit breaker operated by the type cas6 operating mechanism is closed by compressed air and opened by springs.
Technical paper a systematic approach to highvoltage circuit. Purpose share status on replacement of sf6 with environmentally friendly insulating gas for high voltage gis and breakers. The interrupter containers of the minimum oil breakers are made of insulating material and are insulated from the ground. Bulk oil circuit breaker 1bushing, 2 oil level indicator, 3vent, 4current transformer, 5dashpot, 6plunger guide, 7arc control device, 8resistor, 9plunger bar. Control manual switch for local operation in the absence of dc supply. Hv circuit breaker type generator circuit breaker fkga8 generator circuit breaker i sc 210 ka u r 33 kv sf 6 circuit breaker designed for power plants from 700 to 1,500 mw it is equipped with a springoperated mechanism per pole. Oil has to be replaced after some operations because of the carbonization of oil. Inspection, testing and commissioning of electrical. The quantity of oil requires for arc extinction is only about onetenth of the total and the rest being used for the insulation. Whenever there is a separation of current carrying contacts in the oil, the arc in circuit breaker is initialized at the moment of separation of contacts, and due to this arc the oil is vaporized and decomposed in mostly hydrogen gas and. Oil circuit breakerclassification of circuit breakers. Oil circuit breaker bulk and minimum oil circuit breaker.