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Sunday, August 14, 2022

African-American culture

From Wikipedia, the free encyclopedia
 
The National Museum of African American History and Culture is a Smithsonian Institution museum established in December 2003. It is located in Washington, D.C.

African-American culture refers to the contributions of African Americans to the culture of the United States, either as part of or distinct from mainstream American culture. The distinct identity of African-American culture is rooted in the historical experience of the African-American people, including the Middle Passage. The culture is both distinct and enormously influential on American and global worldwide culture as a whole.

African-American culture is rooted in the blend between the native African cultures of West Africa and Central Africa and the European culture that has influenced and modified its development in the American South. Understanding its identity within the culture of the United States, that is, in the anthropological sense, conscious of its origins as largely a blend of West and Central African cultures. Although slavery greatly restricted the ability for Africans to practice their original cultural traditions, many practices, values and beliefs survived, and over time have modified and/or blended with European cultures and other cultures such as that of Native Americans. African-American identity was established during the period of slavery, producing a dynamic culture that has had and continues to have a profound impact on American culture as a whole, as well as that of the broader world.

Elaborate rituals and ceremonies were a significant part of African-Americans' ancestral culture. Many West African societies traditionally believed that spirits dwelled in their surrounding nature. From this disposition, they treated their environment with mindful care. They also generally believed that a spiritual life source existed after death and that ancestors in this spiritual realm could then mediate between the supreme Creator and the living. Honor and prayer were displayed to these "ancient ones", the spirit of that past. West Africans also believed in spiritual possession.

At the beginning of the 18th century, Christianity began to spread across North Africa; this shift in religion began displacing traditional spiritual practices from Africa. The enslaved Africans brought this complex religious dynamic within their culture to America. This fusion of traditional beliefs from Africa with Christianity provided a commonplace for those practicing religion in Africa and America.

After emancipation, unique African-American traditions have continued to flourish, as distinctive traditions or radical innovations in music, art, literature, religion, cuisine, and other fields. 20th-century sociologists, such as Gunnar Myrdal, believed that African-Americans had lost most of their cultural ties with Africa. But, anthropological field research by Melville Herskovits and others demonstrated that there has been a continuum of African traditions among Africans of the diaspora. The greatest influence of African cultural practices on European culture is found below the Mason-Dixon line in the American South.

For many years African-American culture developed separately from American culture, due to enslavement, racial discrimination, and the persistence of African-Americans to make and maintain their own traditions. Today, African-American culture has influenced American culture and yet still remains a distinct cultural body.

African-American culture is influenced by the culture of the Southern United States. Their food and language is influenced by White Southerners who enslaved them on plantations in the South.

African-American cultural history

African American slaves in Georgia, 1850

From the earliest days of American slavery in the 17th century, slave owners sought to exercise control over their slaves by attempting to strip them of their African culture. The physical isolation and societal marginalization of African slaves and, later, of their free progeny, however, facilitated the retention of significant elements of traditional culture among Africans in the New World generally, and in the United States in particular. Slave owners deliberately tried to repress independent political or cultural organization in order to deal with the many slave rebellions or acts of resistance that took place in the United States, Brazil, Haiti, and the Dutch Guyanas.

African cultures, slavery, slave rebellions, and the civil rights movement have shaped African-American religious, familial, political, and economic behaviors. The imprint of Africa is evident in a myriad of ways: in politics, economics, language, music, hairstyles, fashion, dance, religion, cuisine, and worldview.

In turn, African-American culture has had a pervasive, transformative impact on many elements of mainstream American culture. This process of mutual creative exchange is called creolization. Over time, the culture of African slaves and their descendants has been ubiquitous in its impact on not only the dominant American culture, but on world culture as well.

Oral tradition

Slaveholders limited or prohibited education of enslaved African-Americans because they feared it might empower their chattel and inspire or enable emancipatory ambitions. In the United States, the legislation that denied slaves formal education likely contributed to their maintaining a strong oral tradition, a common feature of indigenous or native African culture. African-based oral traditions became the primary means of preserving history, mores, and other cultural information among the people. This was consistent with the griot practices of oral history in many native African culture and other cultures that did not rely on the written word. Many of these cultural elements have been passed from generation to generation through storytelling. The folktales provided African-Americans the opportunity to inspire and educate one another.

Examples of African American folktales include trickster tales of Br'er Rabbit and heroic tales such as that of John Henry. The Uncle Remus stories by Joel Chandler Harris helped to bring African-American folk tales into mainstream adoption. Harris did not appreciate the complexity of the stories nor their potential for a lasting impact on society. Other narratives that appear as important, recurring motifs in African-American culture are the "Signifying Monkey", "The Ballad of Shine", and the legend of Stagger Lee.

The legacy of the African-American oral tradition manifests in diverse forms. African-American preachers tend to perform rather than simply speak. The emotion of the subject is carried through the speaker's tone, volume, and cadence, which tend to mirror the rising action, climax, and descending action of the sermon. The meaning of this manner of preaching is not easily understood by European Americans or others of non-African origin. Often song, dance, verse, and structured pauses are placed throughout the sermon. Call and response is another element of the African-American oral tradition. It manifests in worship in what is commonly referred to as the "amen corner". In direct contrast to the tradition present in American and European cultures, it is an acceptable and common audience reaction to interrupt and affirm the speaker. This pattern of interaction is also in evidence in music, particularly in blues and jazz forms. Hyperbolic and provocative, even incendiary, rhetoric is another aspect of African-American oral tradition often evident in the pulpit in a tradition sometimes referred to as "prophetic speech".

Modernity and migration of African American communities to the North has had a history of placing strain on the retention of African American cultural practices and traditions. The urban and radically different spaces in which black culture was being produced raised fears in anthropologists and sociologists that the southern African American folk aspect of black popular culture were at risk of being lost in history. The study over the fear of losing black popular cultural roots from the South have a topic of interest to many anthropologists, who among them include Zora Neale Hurston. Through her extensive studies of Southern folklore and cultural practices, Hurston has claimed that the popular Southern folklore traditions and practices are not dying off. Instead they are evolving, developing, and re-creating themselves in different regions.

Other aspects of African-American oral tradition include the dozens, signifying, trash talk, rhyming, semantic inversion and word play, many of which have found their way into mainstream American popular culture and become international phenomena.

Spoken-word poetry is another example of how the African-American oral tradition has influenced modern popular culture. Spoken-word artists employ the same techniques as African-American preachers including movement, rhythm, and audience participation. Rap music from the 1980s and beyond has been seen as an extension of African oral culture.

Harlem Renaissance

Zora Neale Hurston was a prominent literary figure during the Harlem Renaissance
 

The first major public recognition of African-American culture occurred during the Harlem Renaissance pioneered by Alain Locke. In the 1920s and 1930s, African-American music, literature, and art gained wide notice. Authors such as Zora Neale Hurston and Nella Larsen and poets such as Langston Hughes, Claude McKay, and Countee Cullen wrote works describing the African-American experience. Jazz, swing, blues and other musical forms entered American popular music. African-American artists such as William H. Johnson, Aaron Douglas, and Palmer Hayden created unique works of art featuring African Americans.

The Harlem Renaissance was also a time of increased political involvement for African Americans. Among the notable African-American political movements founded in the early 20th century are the Universal Negro Improvement Association and the National Association for the Advancement of Colored People. The Nation of Islam, a notable quasi-Islamic religious movement, also began in the early 1930s.

African-American cultural movement

The Black Power movement of the 1960s and 1970s followed in the wake of the non-violent Civil Rights Movement. The movement promoted racial pride and ethnic cohesion in contrast to the focus on integration of the Civil Rights Movement, and adopted a more militant posture in the face of racism. It also inspired a new renaissance in African-American literary and artistic expression generally referred to as the African-American or "Black Arts Movement".

The works of popular recording artists such as Nina Simone ("Young, Gifted and Black") and The Impressions ("Keep On Pushing"), as well as the poetry, fine arts, and literature of the time, shaped and reflected the growing racial and political consciousness. Among the most prominent writers of the African-American Arts Movement were poet Nikki Giovanni; poet and publisher Don L. Lee, who later became known as Haki Madhubuti; poet and playwright Leroi Jones, later known as Amiri Baraka; and Sonia Sanchez. Other influential writers were Ed Bullins, Dudley Randall, Mari Evans, June Jordan, Larry Neal, and Ahmos Zu-Bolton.

Another major aspect of the African-American Arts Movement was the infusion of the African aesthetic, a return to a collective cultural sensibility and ethnic pride that was much in evidence during the Harlem Renaissance and in the celebration of Négritude among the artistic and literary circles in the US, Caribbean, and the African continent nearly four decades earlier: the idea that "black is beautiful". During this time, there was a resurgence of interest in, and an embrace of, elements of African culture within African-American culture that had been suppressed or devalued to conform to Eurocentric America. Natural hairstyles, such as the afro, and African clothing, such as the dashiki, gained popularity. More importantly, the African-American aesthetic encouraged personal pride and political awareness among African Americans.

Music

 
Composer Duke Ellington, pictured receiving the Presidential Medal of Freedom from Richard Nixon, is often held to be one of the most influential musical figures of the 20th century.

African-American music is rooted in the typically polyrhythmic music of the ethnic groups of Africa, specifically those in the Western, Sahelean, and Central and Southern regions. African oral traditions, nurtured in slavery, encouraged the use of music to pass on history, teach lessons, ease suffering, and relay messages. The African pedigree of African-American music is evident in some common elements: call and response, syncopation, percussion, improvisation, swung notes, blue notes, the use of falsetto, melisma, and complex multi-part harmony. During slavery, Africans in America blended traditional European hymns with African elements to create spirituals. The banjo was the first African derived instrument to be played and built in the United States. Slaveholders discovered African-American slaves used drums to communicate.

Many African Americans sing "Lift Every Voice and Sing" in addition to the American national anthem, "The Star-Spangled Banner", or in lieu of it. Written by James Weldon Johnson and John Rosamond Johnson in 1900 to be performed for the birthday of Abraham Lincoln, the song was, and continues to be, a popular way for African Americans to recall past struggles and express ethnic solidarity, faith, and hope for the future. The song was adopted as the "Negro National Anthem" by the NAACP in 1919. Many African-American children are taught the song at school, church or by their families. "Lift Ev'ry Voice and Sing" traditionally is sung immediately following, or instead of, "The Star-Spangled Banner" at events hosted by African-American churches, schools, and other organizations.

In the 19th century, as the result of the blackface minstrel show, African-American music entered mainstream American society. By the early 20th century, several musical forms with origins in the African-American community had transformed American popular music. Aided by the technological innovations of radio and phonograph records, ragtime, jazz, blues, and swing also became popular overseas, and the 1920s became known as the Jazz Age. The early 20th century also saw the creation of the first African-American Broadway shows, films such as King Vidor's Hallelujah!, and operas such as George Gershwin's Porgy and Bess.

Rock and roll, doo wop, soul, and R&B developed in the mid-20th century. These genres became very popular in white audiences and were influences for other genres such as surf. During the 1970s, the dozens, an urban African-American tradition of using rhyming slang to put down one's enemies (or friends), and the West Indian tradition of toasting developed into a new form of music. In the South Bronx the half speaking, half singing rhythmic street talk of "rapping" grew into the hugely successful cultural force known as hip hop.

Contemporary

Contemporary African American hip hop artist Lil Wayne

Hip hop and contemporary R&B would become a multicultural movement, however, it still remained important to many African Americans. The African-American Cultural Movement of the 1960s and 1970s also fueled the growth of funk and later hip hop forms such as rap, hip house, new jack swing, and go-go. House music was created in black communities in Chicago in the 1980s. African-American music has experienced far more widespread acceptance in American popular music in the 21st century than ever before. In addition to continuing to develop newer musical forms, modern artists have also started a rebirth of older genres in the form of genres such as neo soul and modern funk-inspired groups.

Famous contemporary African American musicians include 50 Cent, Jay-Z, Alicia Keys, Usher, Mary J. Blige, Ne-Yo, Snoop Dogg and Kanye West.

The arts

Dance

An African American man breakdancing

African-American dance, like other aspects of African-American culture, finds its earliest roots in the dances of the hundreds of African ethnic groups that made up the enslaved African population in the Americas as well as in traditional folk dances from Europe. Dance in the African tradition, and thus in the tradition of slaves, was a part of both everyday life and special occasions. Many of these traditions such as get down, ring shouts, and other elements of African body language survive as elements of modern dance.

In the 19th century, African-American dance began to appear in minstrel shows. These shows often presented African Americans as caricatures for ridicule to large audiences. The first African-American dance to become popular with white dancers was the cakewalk in 1891. Later dances to follow in this tradition include the Charleston, the Lindy Hop, the Jitterbug and the swing.

During the Harlem Renaissance, African-American Broadway shows such as Shuffle Along helped to establish and legitimize African-American dancers. African-American dance forms such as tap, a combination of African and European influences, gained widespread popularity thanks to dancers such as Bill Robinson and were used by leading white choreographers, who often hired African-American dancers.

Contemporary African-American dance is descended from these earlier forms and also draws influence from African and Caribbean dance forms. Groups such as the Alvin Ailey American Dance Theater have continued to contribute to the growth of this form. Modern popular dance in America is also greatly influenced by African-American dance. American popular dance has also drawn many influences from African-American dance most notably in the hip-hop genre.

One of the uniquely African-American forms of dancing, turfing, emerged from social and political movements in the East Bay in the San Francisco Bay Area. Turfing is a hood dance and a response to the loss of African-American lives, police brutality, and race relations in Oakland, California. The dance is an expression of Blackness, and one that integrates concepts of solidarity, social support, peace, and the discourse of the state of black people in our current social structures.

Twerking is an African-American dance similar to dances from Africa in Cote d’Ivoire, Senegal, Somalia and the Congo.

Art

Midnight Golfer by Eugene J. Martin, mixed-media collage on rag paper

From its early origins in slave communities, through the end of the 20th century, African-American art has made a vital contribution to the art of the United States. During the period between the 17th century and the early 19th century, art took the form of small drums, quilts, wrought-iron figures, and ceramic vessels in the southern United States. These artifacts have similarities with comparable crafts in West and Central Africa. In contrast, African-American artisans like the New England–based engraver Scipio Moorhead and the Baltimore portrait painter Joshua Johnson created art that was conceived in a thoroughly western European fashion.

During the 19th century, Harriet Powers made quilts in rural Georgia, United States that are now considered among the finest examples of 19th-century Southern quilting. Later in the 20th century, the women of Gee's Bend developed a distinctive, bold, and sophisticated quilting style based on traditional African-American quilts with a geometric simplicity that developed separately but was like that of Amish quilts and modern art.

After the American Civil War, museums and galleries began more frequently to display the work of African-American artists. Cultural expression in mainstream venues was still limited by the dominant European aesthetic and by racial prejudice. To increase the visibility of their work, many African-American artists traveled to Europe where they had greater freedom. It was not until the Harlem Renaissance that more European Americans began to pay attention to African-American art in America.

During the 1920s, artists such as Raymond Barthé, Aaron Douglas, Augusta Savage, and photographer James Van Der Zee became well known for their work. During the Great Depression, new opportunities arose for these and other African-American artists under the WPA. In later years, other programs and institutions, such as the New York City-based Harmon Foundation, helped to foster African-American artistic talent. Augusta Savage, Elizabeth Catlett, Lois Mailou Jones, Romare Bearden, Jacob Lawrence, and others exhibited in museums and juried art shows, and built reputations and followings for themselves.

In the 1950s and 1960s, there were very few widely accepted African-American artists. Despite this, The Highwaymen, a loose association of 27 African-American artists from Ft. Pierce, Florida, created idyllic, quickly realized images of the Florida landscape and peddled some 50,000 of them from the trunks of their cars. They sold their art directly to the public rather than through galleries and art agents, thus receiving the name "The Highwaymen". Rediscovered in the mid-1990s, today they are recognized as an important part of American folk history. Their artwork is widely collected by enthusiasts and original pieces can easily fetch thousands of dollars in auctions and sales.

The Black Arts Movement of the 1960s and 1970s was another period of resurgent interest in African-American art. During this period, several African-American artists gained national prominence, among them Lou Stovall, Ed Love, Charles White, and Jeff Donaldson. Donaldson and a group of African-American artists formed the Afrocentric collective AfriCOBRA, which remains in existence today. The sculptor Martin Puryear, whose work has been acclaimed for years, was being honored with a 30-year retrospective of his work at the Museum of Modern Art in New York in November 2007. Notable contemporary African-American artists include Willie Cole, David Hammons, Eugene J. Martin, Mose Tolliver, Reynold Ruffins, the late William Tolliver, and Kara Walker.

Ceramics

In Charleston, South Carolina, thirteen colonoware from the 18th century were found with folded strip roulette decorations. From the time of colonial America until the 19th century in the United States, African-Americans and their enslaved African ancestors, as well as Native Americans who were enslaved and not enslaved, were creating colonoware of this pottery style. Roulette decorated pottery likely originated in West Africa and in the northern region of Central Africa amid 2000 BCE. The longstanding pottery tradition, from which for the Charleston colonoware derives, likely began its initial development between 800 BCE and 400 BCE in Mali; thereafter, the pottery tradition expanded around 900 CE into the Lake Chad basin, into the southeastern region of Mauritania by 1200 CE, and, by the 19th century CE, expanded southward. More specifically, the pottery style for the Charleston colonoware may have been created by 18th century peoples (e.g., Kanuri people, Hausa people in Kano) of the Kanem–Bornu Empire. Within a broader context, following the 17th century enslavement of western Africans for the farming of rice in South Carolina, the Charleston colonoware may be understood as Africanisms from West/Central Africa, which endured the Middle Passage, and became transplanted into the local culture of colonial-era Lowcountry, South Carolina.

Symbolisms from Africa may have served as identity markers for enslaved African-American creators of stoneware. For example, David Drake’s signature marks (e.g., an "X", a slash) and well as Landrum crosses, which were developed by enslaved African-Americans and appear similar to Kongo cosmograms, are such examples from Edgefield County, South Carolina.

Literature

African-American literature has its roots in the oral traditions of African slaves in America. The slaves used stories and fables in much the same way as they used music. These stories influenced the earliest African-American writers and poets in the 18th century such as Phillis Wheatley and Olaudah Equiano. These authors reached early high points by telling slave narratives.

During the early 20th century Harlem Renaissance, numerous authors and poets, such as Langston Hughes, W. E. B. Du Bois, and Booker T. Washington, grappled with how to respond to discrimination in America. Authors during the Civil Rights Movement, such as Richard Wright, James Baldwin, and Gwendolyn Brooks wrote about issues of racial segregation, oppression, and other aspects of African-American life. This tradition continues today with authors who have been accepted as an integral part of American literature, with works such as Roots: The Saga of an American Family by Alex Haley, The Color Purple by Alice Walker, Beloved by Nobel Prize-winning Toni Morrison, and fiction works by Octavia Butler and Walter Mosley. Such works have achieved both best-selling and/or award-winning status.

Cinema

African-American films typically feature an African-American cast and are targeted at an African-American audience. More recently, Black films feature multicultural casts, and are aimed at multicultural audiences, even if American Blackness is essential to the storyline.

Museums

An African American museum in Texas
 

The African-American Museum Movement emerged during the 1950s and 1960s to preserve the heritage of the African-American experience and to ensure its proper interpretation in American history. Museums devoted to African-American history are found in many African-American neighborhoods. Institutions such as the African American Museum and Library at Oakland, The African American Museum in Cleveland and the Natchez Museum of African American History and Culture were created by African Americans to teach and investigate cultural history that, until recent decades, was primarily preserved through oral traditions.

Other prominent African-American museums include Chicago's DuSable Museum of African American History, and the National Museum of African American History and Culture, established in 2003 as part of the Smithsonian Institution in Washington, D.C.

Language

Generations of hardships created by the compounded institutions of slavery imposed on the African-American community which prevented them from learning to read, write English or be educated created distinctive language patterns. Slave owners often intentionally mixed people who spoke different African languages to discourage communication in any language other than English. This, combined with prohibitions against education, led to the development of pidgins, simplified mixtures of two or more languages that speakers of different languages could use to communicate. Examples of pidgins that became fully developed languages include Creole, common to Louisiana, and Gullah, common to the Sea Islands off the coast of South Carolina and Georgia.

African-American Vernacular English (AAVE) is a variety (dialect, ethnolect, and sociolect) of the American English language closely associated with the speech of, but not exclusive to, African Americans. While AAVE is academically considered a legitimate dialect because of its logical structure, some of both whites and African Americans consider it slang or the result of a poor command of Standard American English. Many African Americans who were born outside the American South still speak with hints of AAVE or southern dialect. Inner-city African-American children who are isolated by speaking only AAVE sometimes have more difficulty with standardized testing and, after school, moving to the mainstream world for work. It is common for many speakers of AAVE to code switch between AAVE and Standard American English depending on the setting.

Fashion and aesthetics

Attire

Rapper Kanye West in 2011 wearing hip hop fashion. Hip hop fashion is popular among African Americans. Kanye West is an African American fashion designer for Adidas Yeezy.

The Black Arts Movement, a cultural explosion of the 1960s, saw the incorporation of surviving cultural dress with elements from modern fashion and West African traditional clothing to create a uniquely African-American traditional style. Kente cloth is the best known African textile. These colorful woven patterns, which exist in numerous varieties, were originally made by the Ashanti and Ewe peoples of Ghana and Togo. Kente fabric also appears in a number of Western style fashions ranging from casual T-shirts to formal bow ties and cummerbunds. Kente strips are often sewn into liturgical and academic robes or worn as stoles. Since the Black Arts Movement, traditional African clothing has been popular amongst African Americans for both formal and informal occasions. Other manifestations of traditional African dress in common evidence in African-American culture are vibrant colors, mud cloth, trade beads and the use of Adinkra motifs in jewelry and in couture and decorator fabrics.

Another common aspect of fashion in African-American culture involves the appropriate dress for worship in the Black church. It is expected in most churches that an individual present their best appearance for worship. African-American women in particular are known for wearing vibrant dresses and suits. An interpretation of a passage from the Christian Bible, "...every woman who prays or prophesies with her head uncovered dishonors her head...", has led to the tradition of wearing elaborate Sunday hats, sometimes known as "crowns".

Hip hop fashion is popular with African Americans. Grillz were made popular by African American rapper Nelly. Sagging pants was a part of African American culture. Air Jordan, a shoe brand named after former African American basketball player Michael Jordan, is very popular among the African-American community.

African American fashion designers include Sean Combs, Kimora Lee Simmons, Virgil Abloh and Kanye West.

Hair

Singer Jill Scott wearing a afro in 2012.

Hair styling in African-American culture is greatly varied. African-American hair is typically composed of coiled curls, which range from tight to wavy. Many women choose to wear their hair in its natural state. Natural hair can be styled in a variety of ways, including the afro, twist outs, braid outs, and wash and go styles. It is a myth that natural hair presents styling problems or is hard to manage; this myth seems prevalent because mainstream culture has, for decades, attempted to get African-American women to conform to its standard of beauty (i.e., straight hair). To that end, some women prefer straightening of the hair through the application of heat or chemical processes. Although this can be a matter of personal preference, the choice is often affected by straight hair being a beauty standard in the West and the fact that hair type can affect employment. However, more and more women are wearing their hair in its natural state and receiving positive feedback. Alternatively, the predominant and most socially acceptable practice for men is to leave one's hair natural.

Often, as men age and begin to lose their hair, the hair is either closely cropped, or the head is shaved completely free of hair. However, since the 1960s, natural hairstyles, such as the afro, braids, waves, fades, and dreadlocks, have been growing in popularity. Despite their association with radical political movements and their vast difference from mainstream Western hairstyles, the styles have attained considerable, but certainly limited, social acceptance.

Maintaining facial hair is more prevalent among African-American men than in other male populations in the US. In fact, the soul patch is so named because African-American men, particularly jazz musicians, popularized the style. The preference for facial hair among African-American men is due partly to personal taste, but also because they are more prone than other ethnic groups to develop a condition known as pseudofolliculitis barbae, commonly referred to as razor bumps, many prefer not to shave.

Body image

European-Americans have sometimes appropriated different hair braiding techniques and other forms of African-American hair. There are also individuals and groups who are working towards raising the standing of the African aesthetic among African Americans and internationally as well. This includes efforts toward promoting as models those with clearly defined African features; the mainstreaming of natural hairstyles; and, in women, fuller, more voluptuous body types.

Religion

While African Americans practice a number of religions, Protestant Christianity is by far the most prevalent (more than 85%).

Christianity

A river baptism in New Bern, North Carolina, near the turn of the 20th century
 

The religious institutions of African-American Christians are commonly and collectively referred to as the black church. During the era of slavery, many slaves were stripped of their African belief systems and typically denied free religious practice, forced to become Christians. However, slaves managed to hang on to some of their traditional African religious practices by integrating them into Christian worship during secret meetings. These practices, including dance, shouts, African rhythms, and enthusiastic singing, remain a large part of worship in the African-American church.

African-American churches taught the belief that all people were equal in God's eyes and they also believed that the doctrine of obedience to one's master which was taught in white churches was hypocritical – yet they accepted and propagated internal hierarchies and supported the corporal punishment of children among other things. Instead, the African-American church focused on the message of equality and hopes for a better future. Before and after emancipation, racial segregation in America prompted the development of organized African-American denominations. The first of these was the AME Church founded by Richard Allen in 1787.

After the Civil War the merger of three smaller Baptist groups formed the National Baptist Convention. This organization is the largest African-American Christian Denomination and the second largest Baptist denomination in the United States. An African-American church is not necessarily a separate denomination. Several predominantly African-American churches exist as members of predominantly white denominations. African-American churches have served to provide African-American people with leadership positions and opportunities to organize that were denied in mainstream American society. Because of this, African-American pastors became the bridge between the African-American and European American communities and they thus played a crucial role during the Civil Rights Movement.

Like many Christians, African-American Christians sometimes participate in or attend a Christmas play. Black Nativity by Langston Hughes is a re-telling of the classic Nativity story with gospel music. Productions can be found in African-American theaters and churches all over the country.

Malcolm X, a notable African American Muslim, became a member of the Nation of Islam but later converted to Sunni Islam.

Islam

Generations before the advent of the Atlantic slave trade, Islam was a thriving religion in West Africa due to its peaceful introduction via the lucrative Trans-Saharan trade between prominent tribes in the southern Sahara and the Arabs and Berbers in North Africa. In his attesting to this fact the West African scholar Cheikh Anta Diop explained: "The primary reason for the success of Islam in Black Africa [...] consequently stems from the fact that it was propagated peacefully at first by solitary Arabo-Berber travelers to certain Black kings and notables, who then spread it about them to those under their jurisdiction". Many first-generation slaves were often able to retain their Muslim identity, their descendants were not. Slaves were either forcibly converted to Christianity as was the case in the Catholic lands or were besieged with gross inconveniences to their religious practice such as in the case of the Protestant American mainland.

In the decades after slavery and particularly during the depression era, Islam reemerged in the form of highly visible and sometimes controversial movements in the African-American community. The first of these of note was the Moorish Science Temple of America, founded by Noble Drew Ali. Ali had a profound influence on Wallace Fard, who later founded the Black nationalist Nation of Islam in 1930. Elijah Muhammad became head of the organization in 1934. Much like Malcolm X, who left the Nation of Islam in 1964, many African-American Muslims now follow traditional Islam.

Many former members of the Nation of Islam converted to Sunni Islam when Warith Deen Mohammed took control of the organization after his father's death in 1975 and taught its members the traditional form of Islam based on the Qur'an. A survey by the Council on American-Islamic Relations shows that 30% of Sunni Mosque attendees are African Americans. In fact, most African-American Muslims are orthodox Muslims, as only 2% are of the Nation of Islam.

Judaism

There are 150,000 African Americans in the United States who practice Judaism. Some of these are members of mainstream Jewish groups like the Reform, Conservative, or Orthodox branches of Judaism; others belong to non-mainstream Jewish groups like the Black Hebrew Israelites. The Black Hebrew Israelites are a collection of African-American religious organizations whose practices and beliefs are partially derived from Judaism. Their varied teachings often include the belief that African Americans are descended from the biblical Israelites.

In the last 10 to 15 years, studies have shown that there has been a major increase in the number of African-Americans who identify themselves as being Jewish. Rabbi Capers Funnye, the first cousin of Michelle Obama, says in response to skepticism by some on people being African-American and Jewish at the same time, "I am a Jew, and that breaks through all color and ethnic barriers."

Other religions

Aside from Christianity, Islam, and Judaism, there are also African Americans who practice Buddhism and a number of other religions. There is a small but growing number of African Americans who participate in African traditional religions, such as West African Vodun, Santería, Hoodoo, Ifá and diasporic traditions like the Rastafari movement. Many of them are immigrants or the descendants of immigrants from the Caribbean and South America, where these are practiced. Because of religious practices, such as animal sacrifice, which are no longer common among the larger American religions, these groups may be negatively viewed and they are sometimes the victims of harassment. It must be stated, however, that since the Supreme Court judgement that was given to the Lukumi Babaluaye church of Florida in 1993, there has been no major legal challenge to their right to function as they see fit.

In Louisiana, some African Americans practice Louisiana Voodoo.

Irreligious beliefs

In a 2008 Pew Forum survey, 12% of African Americans described themselves as being nothing in particular (11%), agnostic (1%), or atheist (<0.5%).

Life events

For most African Americans, the observance of life events follows the pattern of mainstream American culture. While African Americans and whites often lived to themselves for much of American history, both groups generally had the same perspective on American culture. There are some traditions that are unique to African Americans.

Some African Americans have created new rites of passage that are linked to African traditions. Some pre-teen and teenage boys and girls take classes to prepare them for adulthood. These classes tend to focus on spirituality, responsibility, and leadership. Many of these programs are modeled after traditional African ceremonies, with the focus largely on embracing African cultures.

To this day, some African-American couples choose to "jump the broom" as a part of their wedding ceremony. Some sources claim that this practice can be traced back to Ghana. However, other sources argue that the African American tradition of "jumping the broom" is far more similar to the tradition in England. Although, this tradition largely fell out of favor in the African-American community after the end of slavery, it has experienced a slight resurgence in recent years as some couples seek to reaffirm their African heritage.

Funeral traditions tend to vary based on a number of factors, including religion and location, but there are a number of commonalities. Probably the most important part of death and dying in the African-American culture is the gathering of family and friends. Either in the last days before death or shortly after death, typically any friends and family members that can be reached are notified. This gathering helps to provide spiritual and emotional support, as well as assistance in making decisions and accomplishing everyday tasks.

The spirituality of death is very important in African-American culture. A member of the clergy or members of the religious community, or both, are typically present with the family through the entire process. Death is often viewed as transitory rather than final. Many services are called homegoings or homecomings, instead of funerals, based on the belief that the person is going home to the afterlife; "Returning to God" or the earth. The entire end of life process is generally treated as a celebration of the person's life, deeds and accomplishments – the "good things" rather than a mourning of loss. This is most notably demonstrated in the New Orleans jazz funeral tradition where upbeat music, dancing, and food encourage those gathered to be happy and celebrate the homegoing of a beloved friend.

Cuisine

A traditional soul food dinner consisting of fried chicken with macaroni and cheese, collard greens, breaded fried okra and cornbread

In studying of the African American culture, food cannot be left out as one of the mediums to understand their traditions, religion, interaction, and social and cultural structures of their community. Observing the ways they prepare their food and eat their food ever since the enslaved era, reveals about the nature and identity of African American culture in the United States. Derek Hicks examines the origins of "gumbo", which is considered a soul food to many African Americans, in his reference to the intertwinement of food and culture in African American community. No written evidence are found historically about the gumbo or its recipes, so through the African American's nature of orally passing their stories and recipes down, gumbo came to represent their truly communal dish. Gumbo is said to be "an invention of enslaved Africans and African Americans" in Louisiana.

Kennedy Fried Chicken, which is known for serving soul food, has many outlets in African American communities.

The cultivation and use of many agricultural products in the United States, such as yams, peanuts, rice, okra, sorghum, indigo dyes, and cotton, can be traced to African influences. African-American foods reflect creative responses to racial and economic oppression and poverty. Under slavery, African Americans were not allowed to eat better cuts of meat, and after emancipation many were often too poor to afford them. During slavery, many African-Americans would take these sorts of leftover ingredients from their white owners, often less desirable cuts of meats and vegetables, and prepare them into a dish that has consistency between stew and soup. Through sharing of this food in churches with a gathering of their people, they not only shared the food, but also experience, feelings, attachment, and sense of unity that brings the community together.

Soul food, a hearty cuisine commonly associated with African Americans in the South (but also common to African Americans nationwide), makes creative use of inexpensive products procured through farming and subsistence hunting and fishing. Pig intestines are boiled and sometimes battered and fried to make chitterlings, also known as "chitlins". Ham hocks and neck bones provide seasoning to soups, beans and boiled greens.

Other common foods, such as fried chicken and fish, macaroni and cheese, cornbread, and hoppin' john (black-eyed peas and rice) are prepared simply. When the African-American population was considerably more rural than it generally is today, rabbit, opossum, squirrel, and waterfowl were important additions to the diet. Many of these food traditions are especially predominant in many parts of the rural South.

Traditionally prepared soul food is often high in fat, sodium, and starch. Highly suited to the physically demanding lives of laborers, farmhands and rural lifestyles generally, it is now a contributing factor to obesity, heart disease, and diabetes in a population that has become increasingly more urban and sedentary. As a result, more health-conscious African Americans are using alternative methods of preparation, eschewing trans fats in favor of natural vegetable oils and substituting smoked turkey for fatback and other, cured pork products; limiting the amount of refined sugar in desserts; and emphasizing the consumption of more fruits and vegetables than animal protein. There is some resistance to such changes, however, as they involve deviating from long culinary tradition.

Sweet potato pie is a popular soul food dessert.

Other soul foods African Americans cook is chicken and waffles and desserts like banana pudding, peach cobbler, red velvet cake and sweet potato pie. Kool-Aid is considered a soul food beverage.

Okra came from Ethiopia and Eritrea. Rice, common to Lowcountry region of South Carolina and Georgia, was imported from the island of Madagascar. Soul food is similar to gypsy cooking in Europe. The roots of soul food are spread up and down the West Coast of Africa, including countries like Senegal, Guinea, Sierre Leone, Liberia, Ivory Coast, Ghana, Togo, Cameroon, Gabon, Nigeria and Angola, as well as in Western European countries such as Scotland, but the fruits can be found across America.

Holidays and observances

Kwanzaa is an African American holiday.

As with other American racial and ethnic groups, African Americans observe ethnic holidays alongside traditional American holidays. Holidays observed in African-American culture are not only observed by African Americans but are widely considered American holidays. The birthday of noted American civil rights leader Martin Luther King Jr. has been observed nationally since 1983. It is one of four federal holidays named for an individual.

Black History Month is another example of another African-American observance that has been adopted nationally and its teaching is even required by law in some states. Black History Month is an attempt to focus attention on previously neglected aspects of the American history, chiefly the lives and stories of African Americans. It is observed during the month of February to coincide with the founding of the NAACP and the birthdays of Frederick Douglass, a prominent African-American abolitionist, and Abraham Lincoln, the United States president who signed the Emancipation Proclamation.

On June 7, 1979, President Jimmy Carter decreed that June would be the month of black music. For the past 28 years, presidents have announced to Americans that Black Music Month (also called African-American Music Month) should be recognized as a critical part of American heritage. Black Music Month is highlighted with various events urging citizens to revel in the many forms of music from gospel to hip-hop. African-American musicians, singers, and composers are also highlighted for their contributions to the nation's history and culture.

Less-widely observed outside of the African-American community is Emancipation Day popularly known as Juneteenth or Freedom Day, in recognition of the official reading of the Emancipation Proclamation on June 19, 1865, in Texas. Juneteenth is a day when African Americans reflect on their unique history and heritage. It is one of the fastest growing African-American holidays with observances in the United States. Juneteenth was recognized as federal holiday in 2021, and was first observed as such on June 19, 2021.

Another holiday not widely observed outside of the African-American community is the birthday of Malcolm X. The day is observed on May 19 in American cities with a significant African-American population, including Washington, D.C.

Another noted African-American holiday is Kwanzaa. Like Emancipation Day, it is not widely observed outside of the African-American community, although it is growing in popularity with both African-American and African communities. African-American scholar and activist "Maulana" Ron Karenga invented the festival of Kwanzaa in 1966, as an alternative to the increasing commercialization of Christmas. Derived from the harvest rituals of Africans, Kwanzaa is observed each year from December 26 through January 1. Participants in Kwanzaa celebrations affirm their African heritage and the importance of family and community by drinking from a unity cup; lighting red, black, and green candles; exchanging heritage symbols, such as African art; and recounting the lives of people who struggled for African and African-American freedom.

Names

Although many African-American names are common among the larger population of the United States, distinct naming trends have emerged within African-American culture. Prior to the 1950s and 1960s, most African-American names closely resembled those used within European American culture. A dramatic shift in naming traditions began to take shape in the 1960s and 1970s in America. With the rise of the mid-century Civil Rights Movement, there was a dramatic rise in names of various origins. The practice of adopting neo-African or Islamic names gained popularity during that era. Efforts to recover African heritage inspired selection of names with deeper cultural significance. Before this, using African names was uncommon because African Americans were several generations removed from the last ancestor to have an African name, as slaves were often given the names of their enslavers, which were of European origin.

African-American names have origins in many languages including French, Latin, English, Arabic, and African languages. One very notable influence on African-American names is the Muslim religion. Islamic names entered the popular culture with the rise of The Nation of Islam among Black Americans with its focus on civil rights. The popular name "Aisha" has origins in the Qur'an. Despite the origins of these names in the Muslim religion and the place of the Nation of Islam in the civil rights movement, many Muslim names such as Jamal and Malik entered popular usage among Black Americans simply because they were fashionable, and many Islamic names are now commonly used by African Americans regardless of their religion. Names of African origin began to crop up as well. Names like Ashanti, Tanisha, Aaliyah, Malaika have origins in the continent of Africa.

By the 1970s and 1980s, it had become common within the culture to invent new names, although many of the invented names took elements from popular existing names. Prefixes such as La/Le-, Da/De-, Ra/Re-, or Ja/Je- and suffixes such as -ique/iqua, -isha, and -aun/-awn are common, as well as inventive spellings for common names.

Even with the rise of creative names, it is also still common for African Americans to use biblical, historic, or European names.

Family

An African American family in Gainesville, Florida.

When slavery was practiced in the United States, it was common for families to be separated through sale. Even during slavery, however, many African-American families managed to maintain strong familial bonds. Free African men and women, who managed to buy their own freedom by being hired out, who were emancipated, or who had escaped their masters, often worked long and hard to buy the members of their families who remained in bondage and send for them.

Others, separated from blood kin, formed close bonds based on fictive kin; play relations, play aunts, cousins, and the like. This practice, a holdover from African oral traditions such as sanankouya, survived Emancipation, with non-blood family friends commonly accorded the status and titles of blood relations. This broader, more African concept of what constitutes family and community, and the deeply rooted respect for elders that is part of African traditional societies, may be the genesis of the common use of the terms like "cousin" (or "cuz"), "aunt", "uncle", "brother", "sister", "Mother", and "Mama" when addressing other African-American people, some of whom may be complete strangers. https://www.loc.gov/exhibits/african-american-odyssey/free-blacks-in-the-antebellum-period.html

African-American family structure

Immediately after slavery, African-American families struggled to reunite and rebuild what had been taken. As late as 1960, when most African Americans lived under some form of segregation, 78 percent of African-American families were headed by married couples. This number steadily declined during the latter half of the 20th century. For the first time since slavery, a majority of African-American children live in a household with only one parent, typically the mother.

This apparent weakness is balanced by mutual-aid systems established by extended family members to provide emotional and economic support. Older family members pass on social and cultural traditions such as religion and manners to younger family members. In turn, the older family members are cared for by younger family members when they cannot care for themselves. These relationships exist at all economic levels in the African-American community, providing strength and support both to the African-American family and the community.

African Americans are less likely to own a pet.

Interracial marriages have increased for African Americans since Loving Vs. Virginia.

Fifty six percent of African American children are born to unmarried mothers. African American parents are more likely to be strict and to hold demanding standards for behavior. In 1998, 1.4 million African American children lived in a grandparent's home.

Politics and social issues

Since the passing of the Voting Rights Act of 1965, African Americans are voting and being elected to public office in increasing numbers. As of 2008 the United States had approximately 10,000 African-American elected officials. African Americans overwhelmingly associate with the Democratic Party. Only 11 percent of African Americans supported for George W. Bush in the 2004 Presidential Election. In 2016, only 8% of African Americans voted for Republican Donald Trump while 88% of African Americans voted for Democrat Hillary Clinton.

Social issues such as racial profiling, racial disparities in sentencing, higher rates of poverty, lower access to health care and institutional racism in general are important to the African-American community. While the divide on racial and fiscal issues has remained consistently wide for decades, seemingly indicating a wide social divide, African Americans tend to hold the same optimism and concern for America as any other ethnic group.

African-Americans may express political and social sentiments through hip-hop culture, including graffiti, break-dancing, rapping, and more. This cultural movement makes statements about historical, as well as present-day topics like street culture and incarceration, and oftentimes expresses a call for change. Hip-hop artists play a prominent role in activism and in fighting social injustices, and have a cultural role in defining and reflecting on political and social issues.

Prominent leaders in the Black church have demonstrated against gay-rights issues such as gay marriage. This stands in stark contrast to the down-low phenomenon of covert male–male sexual acts. Some within the African-American community take a different position, notably the late Coretta Scott King and the Reverend Al Sharpton. Sharpton, when asked in 2003 whether he supported gay marriage, replied that he might as well have been asked if he supported black marriage or white marriage.

African-American LGBT culture

African American LGBT rapper Lil Nas X

The Black LGBT community refers to the African-American (Black) population who are members of the LGBT community, as a community of marginalized individuals who are further marginalized within their own community. Surveys and research have shown that 80% of African Americans say gays and lesbians endure discrimination compared to the 61% of whites. Black members of the community are not only seen as "other" due to their race, but also due to their sexuality, so they always had to combat racism and homophobia.

Black LGBT first started to be visible during the Harlem Renaissance when a subculture of LGBTQ African-American artists and entertainers emerged. This included people like Alain Locke, Countee Cullen, Langston Hughes, Claude McKay, Wallace Thurman, Richard Bruce Nugent, Bessie Smith, Ma Rainey, Moms Mabley, Mabel Hampton, Alberta Hunter, and Gladys Bentley. Places like Savoy Ballroom and the Rockland Palace hosted drag-ball extravaganzas with prizes awarded for the best costumes. Langston Hughes depicted the balls as "spectacles of color". Historian George Chauncey, author of Gay New York: Gender, Urban Culture, and the Making of the Gay Male World, 1890–1940, wrote that during this period "perhaps nowhere were more men willing to venture out in public in drag than in Harlem".

African-American population centers

African-American neighborhoods are types of ethnic enclaves found in many cities in the United States. The formation of African-American neighborhoods is closely linked to the history of segregation in the United States, either through formal laws, or as a product of social norms. Despite this, African-American neighborhoods have played an important role in the development of nearly all aspects of both African-American culture and broader American culture.

Wealthy African-American communities

Many affluent African-American communities exist today, including the following: Woodmore, Maryland; Hillcrest, Rockland County, New York; Redan and Cascade Heights, Georgia; Mitchellville, Maryland; Converse, Texas, Missouri City, Texas; Desoto, Texas; Quinby, South Carolina; Forest Park, Oklahoma; and Mount Airy, Pennsylvania.

Ghettos

Due to segregated conditions and widespread poverty, some African-American neighborhoods in the United States have been called "ghettos". The use of this term is controversial and, depending on the context, potentially offensive. Despite mainstream America's use of the term "ghetto" to signify a poor urban area populated by ethnic minorities, those living in the area often used it to signify something positive. The African-American ghettos did not always contain dilapidated houses and deteriorating projects, nor were all of its residents poverty-stricken. For many African Americans, the ghetto was "home", a place representing authentic "blackness" and a feeling, passion, or emotion derived from the rising above the struggle and suffering of being of African descent in America.

Langston Hughes relays in the "Negro Ghetto" (1931) and "The Heart of Harlem" (1945): "The buildings in Harlem are brick and stone/And the streets are long and wide,/But Harlem's much more than these alone,/Harlem is what's inside." Playwright August Wilson used the term "ghetto" in Ma Rainey's Black Bottom (1984) and Fences (1987), both of which draw upon the author's experience growing up in the Hill District of Pittsburgh, an African-American ghetto.

Although African-American neighborhoods may suffer from civic disinvestment, with lower-quality schools, less-effective policing and fire protection, there are institutions such as churches and museums and political organizations that help to improve the physical and social capital of African-American neighborhoods. In African-American neighborhoods the churches may be important sources of social cohesion. For some African Americans, the kind spirituality learned through these churches works as a protective factor against the corrosive forces of racism. Museums devoted to African-American history are also found in many African-American neighborhoods.

Many African-American neighborhoods are located in inner cities, and these are the mostly residential neighborhoods located closest to the central business district. The built environment is often row houses or brownstones, mixed with older single-family homes that may be converted to multi-family homes. In some areas there are larger apartment buildings. Shotgun houses are an important part of the built environment of some southern African-American neighborhoods. The houses consist of three to five rooms in a row with no hallways. This African-American house design is found in both rural and urban southern areas, mainly in African-American communities and neighborhoods.

In Black Rednecks and White Liberals, Thomas Sowell suggested that modern urban black ghetto culture is rooted in the white Cracker culture of the North Britons and Scots-Irish who migrated from the generally lawless border regions of Great Britain to the American South, where they formed a redneck culture common to both blacks and whites in the antebellum South. According to Sowell, characteristics of this culture included lively music and dance, violence, unbridled emotions, flamboyant imagery, illegitimacy, religious oratory marked by strident rhetoric, and a lack of emphasis on education and intellectual interests. Sowell asserts that white liberal Americans have perpetuated this "counterproductive and self-destructive lifestyle" among black Americans living in urban ghettos through "the welfare state, and look-the-other-way policing, and smiling at 'gangsta rap.'" (edited) Many members of the ghetto are discredited, and falsely misunderstood. Through influence, the members look at for the "weak links" or those lost to the trap. The aim is to make it out or "run the streets."

Social networks

There are African American social networking websites such as BlackPlanet. Social media is an important political outlet for African Americans. African American teenagers are the biggest users of Instagram and SnapChat.

Saturday, August 13, 2022

Circuit breaker

From Wikipedia, the free encyclopedia

An air circuit breaker for low-voltage (less than 1,000 volt) power distribution switchgear
 
A two-pole miniature circuit breaker
 
Four one-pole miniature circuit breakers

A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk of fire. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation.

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

Origins

An early form of circuit breaker was described by Thomas Edison in an 1879 patent application, although his commercial power distribution system used fuses. Its purpose was to protect lighting circuit wiring from accidental short circuits and overloads. A modern miniature circuit breaker similar to the ones now in use was patented by Brown, Boveri & Cie in 1924. Hugo Stotz, an engineer who had sold his company to BBC, was credited as the inventor on DRP (Deutsches Reichspatent) 458392. Stotz's invention was the forerunner of the modern thermal-magnetic breaker commonly used in household load centers to this day.

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 short-circuit currents produced by networks. Simple air-break manual switches produced hazardous arcs when interrupting high voltages; these gave way to oil-enclosed contacts, and various forms using the directed flow of pressurized air, or pressurized oil, to cool and interrupt the arc. By 1935, the specially constructed circuit breakers used at the Boulder Dam project used eight series breaks and pressurized oil flow to interrupt faults of up to 2,500 MVA, in three cycles of the AC power frequency.

Operation

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

The circuit breaker must first detect a fault condition. In small mains and low 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 usually arranged with protective relay pilot devices to sense a fault condition and to operate the opening mechanism. These typically require a separate power source, such as a battery, although some high-voltage circuit breakers are self-contained with current transformers, protective relays, and an internal control power source.

Once a fault is detected, the circuit breaker contacts must open to interrupt the circuit; this is commonly done using mechanically stored energy contained within the breaker, such as a spring or compressed air to separate the contacts. Circuit breakers may also use the higher current caused by the fault to separate the contacts, such as thermal expansion or a magnetic field. Small circuit breakers typically have a manual control lever to switch off the load or reset a tripped breaker, while larger units use solenoids to trip the mechanism, and electric motors to restore energy to the springs.

The circuit breaker contacts must carry the load current without excessive heating, and must also withstand the heat of the arc produced when interrupting (opening) the circuit. Contacts are made of copper or copper alloys, silver alloys and other highly conductive materials. Service life of the contacts is limited by 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 circuit breakers and high-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 heat) is proportional to the current. This arc must be contained, cooled and extinguished in a controlled way, so that the gap between the contacts can 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 point quenching (contacts open at the zero current time crossing of the AC waveform, effectively breaking no load current at the time of opening. The zero-crossing occurs at twice the line frequency; i.e., 100 times per second for 50 Hz and 120 times per second 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 power to the interrupted circuit.

Arc interruption

Low-voltage miniature circuit breakers (MCB) use air alone to extinguish the arc. These circuit breakers contain so-called arc chutes, a stack of mutually insulated parallel metal plates that divide and cool the arc. By splitting the arc into smaller arcs the arc is cooled down while the arc voltage is increased and serves as an additional impedance that limits the current through the circuit breaker. The current-carrying parts near the contacts provide easy deflection of the arc into the arc chutes by a magnetic force of a current path, although magnetic blowout coils or permanent magnets could also 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 short-circuit rating and nominal voltage of the circuit breaker.

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

Gas (usually sulfur hexafluoride) circuit breakers sometimes stretch the arc using a magnetic field, and then rely upon the dielectric strength of the sulfur hexafluoride (SF6) to quench the stretched arc.

Vacuum circuit breakers have minimal arcing (as there is nothing to ionize other than the contact material). The arc quenches when it is stretched a very small amount (less than 2–3 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 sealed chamber, the escaping of the displaced air thus blowing out the arc.

Circuit breakers are usually able to terminate all current very quickly: typically the arc is extinguished between 30 ms and 150 ms after 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

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

Under short-circuit conditions, the calculated or measured maximum prospective short-circuit current may be many times the normal, rated current of the circuit. When electrical 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 continue. This condition can create conductive ionized gases and molten or vaporized metal, 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 incorporate various features to divide and extinguish the arc.

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

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

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

Standard current ratings

Time till trip versus current as multiple of nominal current

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

For low voltage distribution circuit breakers, International Standards, IEC 60898-1 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 1 A, 2 A, 4 A, 6 A, 10 A, 13 A, 16 A, 20 A, 25 A, 32 A, 40 A, 50 A, 63 A, 80 A, 100 A, and 125 A. The circuit breaker is labeled with the rated current in amperes prefixed by a letter, which indicates the instantaneous tripping current that causes the circuit breaker to trip without intentional time delay expressed in multiples of the rated current:

Type Instantaneous tripping current
B 3-5 times rated current In For example a 10 A device will trip at 30–50 A
C 5 to 10 times In
D 10-20 times In
K 8 to 12 times In

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 In for periods in the order of tens of seconds.

For the protection of loads such as semiconductor devices or measuring circuits using current transformers.

Circuit breakers are also rated by the maximum fault current that they can interrupt; this allows use of more economical devices on systems unlikely to develop the high short-circuit current found on, for example, a large commercial building distribution system.

In the United States, Underwriters Laboratories (UL) certifies equipment ratings, called Series Ratings (or "integrated equipment ratings") for circuit breaker equipment used for buildings. Power circuit breakers and medium- and high-voltage circuit breakers used for industrial or electric power systems are designed and tested to ANSI or IEEE standards in the C37 series. For example, standard C37.16 lists preferred frame size current ratings for power circuit 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 as allowing for more complex protection schemes.

Types

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

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

Low-voltage

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

  • Miniature circuit breaker (MCB)—rated current up to 125 A. Trip characteristics normally not adjustable. Thermal or thermal-magnetic operation. Breakers illustrated above are in this category.
  • Molded Case 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 be mounted in multi-tiers in low-voltage switchboards or switchgear cabinets.

The characteristics of low-voltage circuit breakers are given by international standards such as IEC 947. These circuit breakers are often installed in draw-out enclosures that allow removal and interchange without dismantling the switchgear.

Large low-voltage molded case and power circuit breakers may have electric motor operators so they can open and close under remote control. These may form part of an automatic transfer switch system for standby power.

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

Inside a miniature circuit breaker

The DIN rail-mounted thermal-magnetic miniature circuit breaker is the most common 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 circuit breaker. Also indicates the status of the circuit breaker (On or Off/tripped). Most breakers are designed so they can still trip even if the lever is held or locked in the "on" position. This is sometimes referred to as "free trip" or "positive trip" operation.
  2. Actuator mechanism - forces the contacts together or apart.
  3. Contacts - allow current when touching and break the current when moved apart.
  4. Terminals
  5. Bimetallic strip - separates contacts in response to smaller, longer-term overcurrents
  6. Calibration screw - allows the manufacturer to precisely adjust the trip current of the device after assembly.
  7. Solenoid - separates contacts rapidly in response to high overcurrents
  8. Arc divider/extinguisher

Solid state

Solid-state circuit breakers, also known as digital circuit breakers are a technological innovation which promises advance circuit breaker technology out of the mechanical level, into the electrical. This promises several advantages, such as cutting the circuit in fractions of microseconds, better monitoring of circuit loads and longer lifetimes.

Magnetic

Magnetic circuit breakers use a solenoid (electromagnet) whose pulling force 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 by spring action. They are the most commonly used circuit breakers in the United States.

Thermal-magnetic

Shihlin Electric MCCB with SHT

Thermal magnetic circuit breakers, which are the type found in most distribution boards in Europe and countries with a similar wiring arrangements, incorporate both techniques with the electromagnet responding instantaneously to large surges in current (short circuits) and the bimetallic strip responding to less extreme but 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 time. This allows short current spikes such as are produced when a motor or other non-resistive load is switched on. With very large over-currents during a short circuit, the magnetic element trips the circuit breaker with no intentional additional delay.

Magnetic-hydraulic

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

Large power circuit breakers, applied in circuits of more than 1000 volts, may incorporate hydraulic elements in the contact operating mechanism. Hydraulic energy may be supplied by a pump, or stored in accumulators. These form a distinct type from oil-filled circuit breakers where oil is the arc extinguishing medium.

Common trip (ganged) breakers

Three-pole common trip breaker for supplying a three-phase device. This breaker has a 2 A rating.

To provide simultaneous breaking on multiple circuits from a fault on any one, circuit breakers may be made as a ganged assembly. This is a very common requirement for 3 phase systems, where breaking may be either 3 or 4 pole (solid or switched neutral). Some makers make ganging kits to allow groups of single phase breakers to be interlinked as required.

In the US, where split phase supplies are common, in branch circuits with more than one live conductor, each live conductor must be protected by a breaker pole. To ensure that all live conductors are interrupted when any pole trips, a "common trip" breaker must be used. These may either contain two or three tripping mechanisms within one case, 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.

Separate circuit breakers must never be used for live and neutral, because if the neutral is disconnected while the live conductor 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 (because some RCDs need power to trip). This is why only common trip breakers must be used when neutral wire switching is needed.

Shunt-trip units

A shunt-trip unit appears similar to a normal breaker and the moving actuators are 'ganged' to a normal breaker mechanism to operate together in a similar way, but the shunt trip is a solenoid intended to be operated by an external constant voltage signal, rather than a current, commonly the local mains voltage or   DC. These are often used to cut the power when a high risk 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 breaker.

Medium-voltage

A Siemens air circuit breaker mounted on a motor control cubicle

Medium-voltage circuit breakers rated between 1 and 72 kV may be assembled into metal-enclosed switchgear line ups for indoor use, or may be individual components installed outdoors in a substation. Air-break circuit breakers replaced oil-filled units for indoor applications, but are now themselves being replaced by vacuum circuit breakers (up to about 40.5 kV). Like the high voltage circuit breakers described below, these are also operated by 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 nearly always use separate current sensors and protective relays, instead of relying on built-in thermal or magnetic overcurrent sensors.

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

  • Vacuum circuit breakers—With rated current up to 6,300 A, and higher for generator circuit breakers application (up to 16,000 A & 140 kA). 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 6–10 mm the contacts must part. These are generally applied for voltages up to about 40,500 V, 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 addition their global warming potential is by far lower than SF6 circuit breaker.
  • Air circuit breakers—Rated current up to 6,300 A 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. Often used for main power distribution in large industrial plant, 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 bus 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 mechanism to separate the breaker from its enclosure.

High-voltage

Three single-phase Soviet/Russian 110-kV oil circuit breakers
 
400 kV SF6 live-tank circuit breakers

Electrical power transmission networks are protected and controlled by high-voltage breakers. The definition of high voltage varies but in power transmission work is usually thought to be 72.5 kV or higher, according to a recent definition by the International Electrotechnical Commission (IEC). High-voltage breakers are nearly always solenoid-operated, with current sensing protective relays operated through current transformers. In substations the protective relay scheme can be complex, protecting equipment and buses from various types of overload or ground/earth fault.

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

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

Circuit breakers can be classified as 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 circuit breakers are routinely available with ratings up to 765 kV. 1,200 kV breakers were launched by Siemens in November 2011, followed by ABB in April the following year.

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

High-voltage direct current circuit breakers are still a field of research as of 2015. Such breakers would be useful to interconnect HVDC transmission systems.

Sulfur hexafluoride (SF6) high-voltage

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 be incorporated into compact gas-insulated switchgear. In cold climates, supplemental heating or de-rating of the circuit breakers may be required due to liquefaction of the SF6 gas.

Disconnecting circuit breaker (DCB)

The disconnecting circuit breaker (DCB) was introduced in 2000 and is a high-voltage circuit breaker modeled after 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.

In order to further reduce the required space of substation, as well as simplifying the design and engineering of the substation, a fiber optic current sensor (FOCS) can be integrated with the DCB. A 420 kV DCB with integrated FOCS can reduce a substation's footprint with over 50% compared to a conventional solution of live tank breakers with disconnectors and current transformers, due to reduced material and no additional insulation medium.

Carbon dioxide (CO2) high-voltage

In 2012, ABB presented a 75 kV high-voltage breaker that uses carbon dioxide as the medium to extinguish the arc. The carbon dioxide breaker works on the same principles as an SF6 breaker and can also be 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 cycle.

"Smart" circuit breakers

Several firms have 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 use of the technology to turn on and off appliances, as well as potentially turning off charging of electric cars during periods of high electrical grid load. These devices under research and testing would have wireless capability to monitor the electrical usage in a house via a smartphone app or other means.

Other breakers

Residual current circuit breaker with overcurrent protection

The following types are described in separate articles.

  • Breakers for protections against earth faults too small to trip an over-current device:
    • Residual-current device (RCD), or residual-current circuit breaker (RCCB) — detects current imbalance, but does not provide over-current protection. In the United States and Canada, these are called ground fault circuit interrupters (GFCI).
    • Residual-current circuit breaker with overcurrent protection (RCBO) — combines the functions of a RCD and a MCB in one package. In the United States and Canada, these are called GFCI breakers.
    • Earth leakage circuit breaker (ELCB) — This detects current in the earth wire directly 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 earth by another route - such as via a person on the ground or via plumbing. (also called VOELCB in the UK).
  • Recloser — A type of circuit breaker that closes automatically after a delay. These are used on overhead electric power distribution systems, to prevent short duration faults from causing sustained outages.
  • Polyswitch (polyfuse) — A small device commonly described as an automatically resetting fuse rather than a circuit breaker.

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