how to cut an upload object circut

Automatic circuit protection device

Circuit Billow

Electronic symbol

An air circuit billow for low-voltage (less than i,000 volt) power distribution switchgear

A two-pole miniature circuit billow

4 one-pole miniature excursion breakers

A circuit billow is an electrical rubber device designed to protect an electric circuit from impairment acquired by an overcurrent or short circuit. Its basic function is to interrupt electric current flow to protect equipment and to forestall the run a risk of fire. Dissimilar a fuse, which operates once and and then must be replaced, a excursion breaker can be reset (either manually or automatically) to resume normal functioning.

Circuit breakers are made in varying sizes, from minor devices that protect low-electric current circuits or individual household appliances, to large switchgear designed to protect high voltage circuits feeding an entire urban center. The generic function of a circuit billow, or fuse, as an automated means of removing power from a faulty system, is often abbreviated as OCPD (Over Current Protection Device).

Origins [edit]

An early on class of circuit breaker was described by Thomas Edison in an 1879 patent application, although his commercial power distribution organization used fuses.^[i] Its purpose was to protect lighting circuit wiring from adventitious short circuits and overloads. A modern miniature circuit breaker similar to the ones at present in employ was patented past Brown, Boveri & Cie in 1924. Hugo Stotz, an engineer who had sold his company to BBC, was credited every bit the inventor on DRP (Deutsches Reichspatent) 458392.^[2] Stotz's invention was the forerunner of the modern thermal-magnetic breaker commonly used in household load centers to this 24-hour interval.

Interconnection of multiple generator sources into an electrical grid required the development of circuit breakers with increasing voltage ratings and increased ability to safely interrupt the increasing curt-excursion currents produced by networks. Simple air-break transmission switches produced chancy arcs when interrupting high voltages; these gave way to oil-enclosed contacts, and various forms using the directed menses of pressurized air, or pressurized oil, to cool and interrupt the arc. By 1935, the peculiarly constructed circuit breakers used at the Boulder Dam projection used 8 series breaks and pressurized oil flow to interrupt faults of up to 2,500 MVA, in three cycles of the AC power frequency.^[three]

Performance [edit]

All circuit breaker systems take common features in their operation, just details vary substantially depending on the voltage class, current rating and type of the excursion breaker.

The excursion breaker must first notice a error status. In minor mains and depression voltage circuit breakers, this is usually done within the device itself. Typically, the heating or magnetic effects of electric current are employed. Circuit breakers for large currents or high voltages are commonly bundled with protective relay airplane pilot devices to sense a fault condition and to operate the opening machinery. These typically require a dissever power source, such equally a battery, although some high-voltage circuit breakers are cocky-independent with current transformers, protective relays, and an internal command power source.

Once a fault is detected, the circuit breaker contacts must open to interrupt the circuit; this is commonly washed using mechanically stored free energy contained inside the breaker, such as a jump or compressed air to divide the contacts. Circuit breakers may also utilise the college current caused by the fault to dissever the contacts, such as thermal expansion or a magnetic field. Small-scale circuit breakers typically have a transmission control lever to switch off the load or reset a tripped breaker, while larger units apply solenoids to trip the mechanism, and electrical motors to restore energy to the springs.

The circuit breaker contacts must conduct the load current without excessive heating, and must also withstand the heat of the arc produced when interrupting (opening) the circuit. Contacts are fabricated of copper or copper alloys, silverish alloys and other highly conductive materials. Service life of the contacts is express past the erosion of contact material due to arcing while interrupting the current. Miniature and molded-case circuit breakers are usually discarded when the contacts have worn, but power excursion breakers and loftier-voltage circuit breakers have replaceable contacts.

When a high current or voltage is interrupted, an arc is generated. The length of the arc is generally proportional to the voltage while the intensity (or estrus) is proportional to the electric current. This arc must be contained, cooled and extinguished in a controlled style, and then that the gap betwixt the contacts can once again withstand the voltage in the circuit. Different circuit breakers use vacuum, air, insulating gas, or oil as the medium the arc forms in. Different techniques are used to extinguish the arc including:

• Lengthening or deflecting the arc
• Intensive cooling (in jet chambers)
• Division into partial arcs
• Zero indicate quenching (contacts open at the null current time crossing of the AC waveform, finer breaking no load current at the time of opening. The zero-crossing occurs at twice the line frequency; i.eastward., 100 times per 2d for 50 Hz and 120 times per 2d for 60 Hz AC.)
• Connecting capacitors in parallel with contacts in DC circuits.

Finally, once the fault condition has been cleared, the contacts must again be closed to restore ability to the interrupted circuit.

Arc interruption [edit]

Low-voltage miniature circuit breakers (MCB) utilise air lone to extinguish the arc. These circuit breakers contain so-called arc chutes, a stack of mutually insulated parallel metal plates that split and cool the arc. By splitting the arc into smaller arcs the arc is cooled downwards while the arc voltage is increased and serves as an additional impedance that limits the current through the circuit breaker. The electric current-carrying parts near the contacts provide like shooting fish in a barrel deflection of the arc into the arc chutes by a magnetic force of a electric current path, although magnetic blowout coils or permanent magnets could too deflect the arc into the arc chute (used on circuit breakers for higher ratings). The number of plates in the arc chute is dependent on the curt-excursion rating and nominal voltage of the excursion breaker.

In larger ratings, oil circuit breakers rely upon vaporization of some of the oil to blast a jet of oil through the arc.^[4]

Gas (usually sulfur hexafluoride) excursion breakers sometimes stretch the arc using a magnetic field, and then rely upon the dielectric forcefulness of the sulfur hexafluoride (SF_six) to quench the stretched arc.

Vacuum circuit breakers have minimal arcing (as at that place is cipher to ionize other than the contact textile). The arc quenches when information technology is stretched a very small amount (less than 2–three mm (0.08–0.1 in)). Vacuum circuit breakers are frequently used in modern medium-voltage switch gear to 38,000 volts.

Air circuit breakers may use compressed air to blow out the arc, or alternatively, the contacts are rapidly swung into a small-scale sealed chamber, the escaping of the displaced air thus bravado out the arc.

Circuit breakers are normally able to terminate all electric current very speedily: typically the arc is extinguished between 30 ms and 150 ms later on the mechanism has been tripped, depending upon age and construction of the device. The maximum current value and let-through energy determine the quality of the circuit breakers.

Short circuit [edit]

Circuit breakers are rated both past the normal current that they are expected to carry, and the maximum curt-circuit electric current that they tin safely interrupt. This latter figure is the ampere interrupting capacity (AIC) of the breaker.

Under short-excursion conditions, the calculated or measured maximum prospective short-circuit electric current may be many times the normal, rated current of the circuit. When electric contacts open to interrupt a large current, there is a tendency for an arc to form between the opened contacts, which would allow the current to proceed. This condition can create conductive ionized gases and molten or vaporized metallic, which can cause the further continuation of the arc, or creation of additional short circuits, potentially resulting in the explosion of the circuit breaker and the equipment that it is installed in. Therefore, circuit breakers must contain various features to divide and extinguish the arc.

The maximum brusque-circuit current that a breaker tin can interrupt is determined by testing. Application of a breaker in a circuit with a prospective short-circuit current college than the breaker's interrupting chapters rating may result in failure of the breaker to safely interrupt a fault. In a worst-instance scenario, the breaker may successfully interrupt the fault, only to explode when reset.

Typical domestic console circuit breakers are rated to interrupt 6 kA ( 6000 A) short-circuit current.

Miniature circuit breakers used to protect control circuits or small appliances may not have sufficient interrupting chapters to apply at a panel board; these circuit breakers are called "supplemental circuit protectors" to distinguish them from distribution-type circuit breakers.

Standard current ratings [edit]

Time till trip versus current every bit multiple of nominal current

Circuit breakers are manufactured in standard sizes, using a system of preferred numbers to encompass a range of ratings. Miniature circuit breakers accept a fixed trip setting; changing the operating current value requires changing the whole circuit breaker. Larger circuit breakers tin can have adjustable trip settings, allowing standardized elements to be practical but with a setting intended to meliorate protection. For example, a circuit breaker with a 400 ampere "frame size" might take its overcurrent detection set up to operate at only 300 amperes, to protect a feeder cable.

For depression voltage distribution circuit breakers, International Standards, IEC 60898-one defines the rated current as the maximum current that the breaker is designed to carry continuously. The commonly available preferred values for the rated current are iA, 2A, fourA, half dozen A, 10 A, 13 A, 16 A, 20 A, 25 A, 32 A, 40 A, fifty A, 63 A, fourscore A, 100 A,^[5] and 125 A. The excursion breaker is labeled with the rated current in amperes prefixed by a alphabetic character, which indicates the instantaneous tripping current that causes the circuit breaker to trip without intentional fourth dimension delay expressed in multiples of the rated current:

Type	Instantaneous tripping current
B	3-5 times rated electric current In For example a ten A device will trip at 30–50 A
C	five to 10 times In
D	10-20 times In
K	8 to 12 times Inorthward For the protection of loads that cause frequent short duration (approximately 400 ms to 2 s) current peaks in normal operation.
Z	2 to 3 times I n for periods in the order of tens of seconds. For the protection of loads such as semiconductor devices or measuring circuits using electric current transformers.

Circuit breakers are also rated past the maximum fault current that they can interrupt; this allows use of more than economic devices on systems unlikely to develop the loftier short-circuit current plant on, for example, a large commercial building distribution organization.

In the United States, Underwriters Laboratories (UL) certifies equipment ratings, called Series Ratings (or "integrated equipment ratings") for circuit billow equipment used for buildings. Ability circuit breakers and medium- and high-voltage excursion breakers used for industrial or electrical power systems are designed and tested to ANSI or IEEE standards in the C37 serial. For example, standard C37.16 lists preferred frame size current ratings for ability excursion breakers in the range ofo 600 to 5000 amperes. Trip current settings dn time-current characteristics of these breakers are generally adjustable.

For medium and high voltage circuit breakers used in switchgear or substations and generating stations, relatively few standard frame sizes are generally manufactured. These circuit breakers are usually controlled by separate protective relay systems, offering adjustable tripping current and time settings as well equally assuasive for more circuitous protection schemes.

Types [edit]

Front panel of a 1250 A air circuit breaker manufactured past ABB. This low-voltage ability circuit breaker can be withdrawn from its housing for servicing. Trip characteristics are configurable via DIP switches on the front end panel.

Many classifications of circuit breakers can be made, based on their features such equally voltage class, construction type, interrupting type, and structural features.

Depression-voltage [edit]

Depression-voltage (less than 1,000 V_AC) types are common in domestic, commercial and industrial application, and include:

• Miniature circuit breaker (MCB)—rated current upward to 125 A. Trip characteristics normally non adjustable. Thermal or thermal-magnetic performance. Breakers illustrated above are in this category.
• Molded Example Circuit Breaker (MCCB)—rated current up to 1,600 A. Thermal or thermal-magnetic operation. Trip current may be adjustable in larger ratings.
• Low-voltage power circuit breakers can exist mounted in multi-tiers in low-voltage switchboards or switchgear cabinets.

The characteristics of depression-voltage circuit breakers are given past international standards such equally IEC 947. These circuit breakers are frequently installed in draw-out enclosures that allow removal and interchange without dismantling the switchgear.

Large depression-voltage molded case and power circuit breakers may take electrical motor operators and so they can open and close under remote command. These may form part of an automatic transfer switch system for standby power.

Low-voltage excursion breakers are also made for direct-current (DC) applications, such as DC for subway lines. Direct electric current requires special breakers because the arc is continuous—dissimilar an AC arc, which tends to become out on each half wheel, directly current excursion breaker has blow-out coils that generate a magnetic field that rapidly stretches the arc. Minor circuit breakers are either installed directly in equipment, or are arranged in a breaker panel.

Inside a miniature excursion billow

The DIN rail-mounted thermal-magnetic miniature excursion breaker is the about mutual style in modern domestic consumer units and commercial electrical distribution boards throughout Europe. The design includes the following components:

1. Actuator lever - used to manually trip and reset the excursion breaker. Besides indicates the status of the circuit billow (On or Off/tripped). Well-nigh breakers are designed then they tin even so trip even if the lever is held or locked in the "on" position. This is sometimes referred to equally "complimentary trip" or "positive trip" operation.
2. Actuator mechanism - forces the contacts together or apart.
3. Contacts - allow current when touching and intermission the current when moved autonomously.
4. Terminals
5. Bimetallic strip - separates contacts in response to smaller, longer-term overcurrents
6. Calibration spiral - allows the manufacturer to precisely arrange the trip current of the device later on assembly.
7. Solenoid - separates contacts rapidly in response to high overcurrents
8. Arc divider/extinguisher

Solid land [edit]

Solid-land excursion breakers, as well known as digital excursion breakers are a technological innovation which promises advance circuit billow technology out of the mechanical level, into the electric. This promises several advantages, such every bit cut the circuit in fractions of microseconds, ameliorate monitoring of excursion loads and longer lifetimes.^[6]

Magnetic [edit]

Magnetic excursion breakers use a solenoid (electromagnet) whose pulling forcefulness increases with the current. Certain designs utilize electromagnetic forces in addition to those of the solenoid. The circuit breaker contacts are held closed by a latch. As the current in the solenoid increases beyond the rating of the circuit breaker, the solenoid's pull releases the latch, which lets the contacts open up by spring action. They are the near normally used excursion breakers in the Us.

Thermal-magnetic [edit]

Shihlin Electric MCCB with SHT

Thermal magnetic circuit breakers, which are the type found in near distribution boards in Europe and countries with a similar wiring arrangements, incorporate both techniques with the electromagnet responding instantaneously to large surges in current (curt circuits) and the bimetallic strip responding to less extreme merely longer-term over-current conditions. The thermal portion of the circuit breaker provides a time response feature, that trips the circuit breaker sooner for larger over currents but allows smaller overloads to persist for a longer fourth dimension. This allows brusk current spikes such as are produced when a motor or other not-resistive load is switched on. With very large over-currents during a short circuit, the magnetic chemical element trips the circuit breaker with no intentional additional delay.^[seven]

Magnetic-hydraulic [edit]

A magnetic-hydraulic excursion breaker uses a solenoid gyre to provide operating strength to open the contacts. Magnetic-hydraulic breakers incorporate a hydraulic time filibuster feature using a mucilaginous fluid. A spring restrains the core until the current exceeds the breaker rating. During an overload, the speed of the solenoid move is restricted by the fluid. The filibuster permits brief current surges beyond normal running electric current for motor starting, energizing equipment, etc. Short-circuit currents provide sufficient solenoid force to release the latch regardless of cadre position thus bypassing the delay characteristic. Ambient temperature affects the time filibuster but does not affect the current rating of a magnetic breaker.^[8]

Large power circuit breakers, applied in circuits of more than m volts, may incorporate hydraulic elements in the contact operating mechanism. Hydraulic energy may be supplied past a pump, or stored in accumulators. These form a distinct type from oil-filled circuit breakers where oil is the arc extinguishing medium.^[9]

Common trip (ganged) breakers [edit]

Three-pole common trip billow for supplying a three-phase device. This breaker has a ii A rating.

To provide simultaneous breaking on multiple circuits from a error on whatsoever ane, excursion breakers may be made as a ganged assembly. This is a very common requirement for iii phase systems, where breaking may exist either iii or 4 pole (solid or switched neutral). Some makers make ganging kits to allow groups of single phase breakers to exist interlinked equally required.

In the US, where separate stage supplies are common, in branch circuits with more one live usher, each live conductor must be protected past a breaker pole. To ensure that all alive conductors are interrupted when any pole trips, a "mutual trip" breaker must be used. These may either contain 2 or three tripping mechanisms within one example, or for small breakers, may externally tie the poles together via their operating handles. Two-pole common trip breakers are common on 120/240-volt systems where 240 volt loads (including major appliances or further distribution boards) span the two live wires. Three-pole common trip breakers are typically used to supply three-phase electric power to large motors or further distribution boards.

Carve up excursion breakers must never exist used for live and neutral, because if the neutral is asunder while the alive usher stays connected, a very dangerous condition arises: the circuit appears de-energized (appliances don't work), but wires remain live and some residual-current devices (RCDs) may not trip if someone touches the live wire (considering some RCDs need power to trip). This is why only common trip breakers must exist used when neutral wire switching is needed.

Shunt-trip units [edit]

A shunt-trip unit of measurement appears similar to a normal breaker and the moving actuators are 'ganged' to a normal breaker mechanism to operate together in a like style, but the shunt trip is a solenoid intended to exist operated past an external constant voltage signal, rather than a current, normally the local mains voltage or DC. These are often used to cut the power when a high gamble event occurs, such as a fire or flood alarm, or another electrical condition, such as over voltage detection. Shunt trips may be a user fitted accessory to a standard breaker, or supplied as an integral part of the circuit billow.

Medium-voltage [edit]

A Siemens air circuit breaker mounted on a motor control cubicle

Medium-voltage circuit breakers rated between 1 and 72kV may be assembled into metal-enclosed switchgear line ups for indoor use, or may exist individual components installed outdoors in a substation. Air-break excursion breakers replaced oil-filled units for indoor applications, but are now themselves being replaced by vacuum circuit breakers (upward to almost 40.5kV). Similar the loftier voltage circuit breakers described below, these are also operated past current sensing protective relays operated through current transformers. The characteristics of MV breakers are given by international standards such as IEC 62271. Medium-voltage circuit breakers almost e'er use split up current sensors and protective relays, instead of relying on built-in thermal or magnetic overcurrent sensors.

Medium-voltage excursion breakers can be classified by the medium used to extinguish the arc:

• Vacuum circuit breakers—With rated current up to half dozen,300A, and college for generator excursion breakers application (upward to 16,000A & 140kA). These breakers interrupt the current by creating and extinguishing the arc in a vacuum container - aka "bottle". Long life bellows are designed to travel the 6–x mm the contacts must part. These are generally practical for voltages up to about 40,500V,^[ten] which corresponds roughly to the medium-voltage range of power systems. Vacuum circuit breakers have longer life expectancy between overhaul than do other circuit breakers. In improver their global warming potential is by far lower than SF ₆ circuit breaker.
• Air circuit breakers—Rated electric current upwardly to half dozen,300A and higher for generator circuit breakers. Trip characteristics are often fully adjustable including configurable trip thresholds and delays. Usually electronically controlled, though some models are microprocessor controlled via an integral electronic trip unit of measurement. Often used for main power distribution in large industrial found, where the breakers are arranged in draw-out enclosures for ease of maintenance.
• SF₆ circuit breakers extinguish the arc in a chamber filled with sulfur hexafluoride gas.

Medium-voltage circuit breakers may be connected into the circuit by bolted connections to motorbus bars or wires, especially in outdoor switchyards. Medium-voltage circuit breakers in switchgear line-ups are often built with draw-out construction, allowing breaker removal without disturbing power circuit connections, using a motor-operated or hand-cranked machinery to separate the breaker from its enclosure.

High-voltage [edit]

Iii single-stage Soviet/Russian 110-kV oil circuit breakers

400 kV SF₆ live-tank circuit breakers

Electrical power transmission networks are protected and controlled by loftier-voltage breakers. The definition of high voltage varies just in power manual work is usually idea to be 72.5 kV or college, co-ordinate to a recent definition by the International Electrotechnical Committee (IEC). High-voltage breakers are near always solenoid-operated, with current sensing protective relays operated through electric current transformers. In substations the protective relay scheme tin can be complex, protecting equipment and buses from various types of overload or ground/earth mistake.

Loftier-voltage breakers are broadly classified by the medium used to extinguish the arc:

• Majority oil
• Minimum oil
• Air blast
• Vacuum
• SF_half-dozen
• CO_two

Due to environmental and cost concerns over insulating oil spills, virtually new breakers use SF₆ gas to quench the arc.

Circuit breakers can be classified equally live tank, where the enclosure that contains the breaking mechanism is at line potential, or dead tank with the enclosure at earth potential. High-voltage AC excursion breakers are routinely available with ratings upwards to 765 kV. i,200kV breakers were launched by Siemens in November 2011,^[11] followed by ABB in April the following year.^[12]

Loftier-voltage excursion breakers used on transmission systems may be arranged to permit a unmarried pole of a iii-phase line to trip, instead of tripping all three poles; for some classes of faults this improves the system stability and availability.

High-voltage straight current excursion breakers are still a field of research as of 2015. Such breakers would be useful to interconnect HVDC transmission systems.^[13]

Sulfur hexafluoride (SF₆) loftier-voltage [edit]

A sulfur hexafluoride circuit breaker uses contacts surrounded by sulfur hexafluoride gas to quench the arc. They are most often used for transmission-level voltages and may exist incorporated into meaty gas-insulated switchgear. In cold climates, supplemental heating or de-rating of the circuit breakers may be required due to liquefaction of the SF_{half dozen} gas.

Disconnecting circuit breaker (DCB) [edit]

The disconnecting circuit breaker (DCB) was introduced in 2000^[xiv] and is a high-voltage excursion billow modeled afterward the SF₆-breaker. It presents a technical solution where the disconnecting function is integrated in the breaking chamber, eliminating the need for separate disconnectors. This increases the availability, since open-air disconnecting switch main contacts need maintenance every 2–6 years, while modern circuit breakers have maintenance intervals of 15 years. Implementing a DCB solution also reduces the space requirements within the substation, and increases the reliability, due to the lack of separate disconnectors.^{[15] [sixteen]}

In order to further reduce the required space of substation, too equally simplifying the pattern and engineering of the substation, a fiber optic current sensor (FOCS) tin be integrated with the DCB. A 420 kV DCB with integrated FOCS tin reduce a substation's footprint with over 50% compared to a conventional solution of alive tank breakers with disconnectors and current transformers, due to reduced cloth and no boosted insulation medium.^[17]

Carbon dioxide (CO₂) high-voltage [edit]

In 2012, ABB presented a 75kV high-voltage billow that uses carbon dioxide as the medium to extinguish the arc. The carbon dioxide billow works on the same principles equally an SF_half-dozen billow and can also exist produced as a disconnecting circuit breaker. By switching from SF₆ to CO₂, it is possible to reduce the CO₂ emissions by 10 tons during the product's life bicycle.^[18]

"Smart" circuit breakers [edit]

Several firms take looked at adding monitoring for appliances via electronics or using a digital circuit breaker to monitor the breakers remotely. Utility companies in the United States have been reviewing utilize of the technology to turn on and off appliances, too as potentially turning off charging of electric cars during periods of high electrical grid load. These devices nether research and testing would have wireless capability to monitor the electrical usage in a house via a smartphone app or other ways.^[19]

Other breakers [edit]

The post-obit types are described in separate articles.

• Breakers for protections against earth faults too minor to trip an over-electric current device:
  • Residual-current device (RCD), or rest-current excursion breaker (RCCB) — detects current imbalance, but does not provide over-current protection. In the United states and Canada, these are called ground error circuit interrupters (GFCI).
  • Residue-electric current circuit breaker with overcurrent protection (RCBO) — combines the functions of a RCD and a MCB in ane package. In the The states and Canada, these are called GFCI breakers.
  • Earth leakage circuit breaker (ELCB) — This detects current in the earth wire direct rather than detecting imbalance. They are no longer seen in new installations as they cannot detect any dangerous condition where the current is returning to globe by another route - such as via a person on the ground or via plumbing. (also called VOELCB in the UK).
• Recloser — A blazon of circuit billow that closes automatically later on a filibuster. These are used on overhead electric power distribution systems, to preclude short duration faults from causing sustained outages.
• Polyswitch (polyfuse) — A small device unremarkably described as an automatically resetting fuse rather than a excursion breaker.

Meet also [edit]

• Arc-fault excursion interrupter
• Breaking capacity
• Circuit billow analyzer
• Circuit total limitation (CTL)
• Distribution board (Excursion breaker panel)
• Earthing system
• Ground Fault Circuit Interrupter (GFCI)
• Hybrid switchgear module
• Insulation monitoring device
• Motor control eye (MCC)
• Network protector
• Power distribution middle (PDC)
• Power system protection
• Remote racking organization
• Band Master Unit of measurement
• Selectivity (circuit breakers)
• Stab-Lok—a popular type of circuit breaker manufactured from 1950 to 1990, now widely accounted unsafe
• Sulfur hexafluoride excursion billow
• Zener diode—a diode that allows electric current to flow in reverse direction (to beak at certain level of voltage, an reverse effect)

References [edit]

1. ^ Robert Friedel and Paul Israel, Edison'south Electric Light: Biography of an Invention, Rutgers University Press, New Brunswick New Jersey United states,1986 ISBN 0-8135-1118-6 pp.65-66
2. ^ ""1920-1929 Stotz miniature circuit billow and domestic appliances", ABB, 2006-01-09, accessed 4 July 2011". Archived from the original on 2013-10-29. Retrieved 2011-07-04 .
3. ^ Flurscheim, Charles H., ed. (1982). "Chapter ane". Ability Excursion Billow Theory and Pattern (Second ed.). IET. ISBN0-906048-lxx-ii.
4. ^ Weedy, B. Grand. (1972). Electric Power Systems (Second ed.). London: John Wiley and Sons. pp. 428–430. ISBN0-471-92445-8.
5. ^ "What is an MCB and how does it work?". Consumer Unit World. 16 September 2016. Archived from the original on 11 July 2018. Retrieved 11 July 2018.
6. ^ "Archived copy". Archived from the original on 2022-01-25. Retrieved 2018-xi-fourteen . {{cite spider web}}: CS1 maint: archived re-create every bit title (link)
7. ^ John Matthews Introduction to the Pattern and Assay of Edifice Electric Systems Springer 1993 0442008740 page 86
8. ^ Hwaiyu Geng, Data Center Handbook, John Wiley & Sons,2014 page 542
9. ^ K R Jones (ed), Electrical Engineer'due south Reference Book, Butterworth - Heinemann Ltd, 1993, page 25/14
10. ^ A few manufacturers now offer a single-bottle vacuum billow rated upwards to 72.5kV and even 145kV. See https://www.edu-right.com/full-noesis-near-integrated ^{[ permanent dead link ]} Electric Engineering in India, vol 157 upshot 4 pages 13-23
11. ^ "Siemens launches world'south beginning 1200kV SF6 Circuit Breaker". Archived from the original on 3 July 2013. Retrieved 14 November 2011.
12. ^ "ABB to develop ultra high voltage circuit breaker". Archived from the original on 4 March 2016. Retrieved 14 August 2012.
13. ^ "High Voltage DC Switch Enables Supergrids for Renewable Free energy, MIT Technology Review". Retrieved 19 July 2013.
14. ^ "Applications of Disconnecting Circuit Breakers, Michael Faxå, p.1" (PDF). Archived from the original (PDF) on 16 May 2013. Retrieved nine July 2012.
15. ^ "HPL Disconnecting Circuit Breaker". Archived from the original on xx Feb 2014. Retrieved 9 July 2012.
16. ^ "Disconnecting Circuit Breakers, Buyer's and Application Guide, p. 10" (PDF). Archived (PDF) from the original on 5 December 2020. Retrieved 15 September 2014.
17. ^ "362 – 550 kV Disconnecting Circuit Breaker with FOCS: Pocket-size, smart and flexible, p.i". Archived from the original on 11 May 2020. Retrieved 3 July 2013.
18. ^ "Switzerland: ABB breaks new ground with surround friendly high-voltage circuit breaker". Archived from the original on 24 December 2019. Retrieved 7 June 2013.
19. ^ "Smart excursion-breakers for energy-efficient homes". The Economist. 2017-xi-23. Archived from the original on 2018-01-fifteen. Retrieved 2018-01-15 .

General

• BS EN 60898-1. Electrical accessories — Circuit breakers for over-current protection for household and like installations. British Standards Institution, 2003.

coleuptarterxed.blogspot.com

Source: https://en.wikipedia.org/wiki/Circuit_breaker

Share this post