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the delta has a higher voltage to ground on the B phase and is identified by the orange color for identification means so its easier to smoke equipment if not careful.hardly see delta connections anymore so old school and outdated. it just makes economic sense to use a star connection.
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On the above answer there should be no voltage to ground on a delta connection. All three phase coils are connected in series with each other and at no point in the delta are they grounded. Most of the commercial and industrial motor connections are connected delta. In installations where the motor inrush is above utility company specifications the Star- Delta connection is used. This limits the inrush current in the star configuration and then after a time delay connects the motor in a delta configuration. With delta systems the use of grounding lights are mandatory. These are used to detect if a phase grounds out. One phase and the motor can still be in operation, two grounds represent a short circuit and the system will trip.
CommentThe second answer is not altogether correct... In the USA and Canada, it is common practise for one phase of the delta-connected secondary windings of a three-phase transformer bank, to have an earthed (grounded) centre tap. With each phase providing 240 V; the centre-tapped phase then provides a combination of 240 V line-to-line together with two 120-V line-to-neutral (earth) voltages which is the standard supply method for residences in North America. The point of common connection between the two remaining phases is termed the 'high leg' of that particular transformer connection, having a potential of 208 V with respect to earth (although this is not used). To summarise, this method provides a 240-V three-phase supply, combined with a single-phase 240/120-V supply, which is useful for small businesses (e.g. garages) which might need to operate three-phase motors.
However, the second answer is perfectly true for the UK (and, possibly, elsewhere in Europe) where residences are supplied with just one voltage (230 V) -unlike North America- and delta-connected supplies are relatively unusual.
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∙ 13y ago
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∙ 12y agoIn star connection, identical terminal of each phase are joined together. This is called the neutral terminal. Thus total four wires are brought out. The connection is likely to be with the picture of star, so the connection is called star connection.
Whereas in delta connection, finish end of the first phase is connected to the start end of the second phase and finish end of the second phase is connected to the start of the third phase and the finish end of the third phase is connected to the start of the first phase. From each of the junction one line is brought out, and there is no neutral wire in delta connection. The connection display the similar picture of the delta, so the connection is known as delta connection.
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∙ 13y agoThese are the ways electricity reaches our houses , if u have a three phase supply.
in delata there is no neutral and instra it has one . delta more oftenly is used for motors etc.. since they need no neutral . however for household things u hv to use star ... one phase and a neutral off it ...
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∙ 9y agoDelta connection is better than star connection. Because delta connection provides more power and efficiency than star connection.
Another Answer
Neither is 'better' as they each fulfil the function for which they are used. For example if, as in Europe, you wish to provide two voltages, 400 V (line-to-line) and 230 V (line-to-neutral), single-phase and three-phase, then you might consider the star connection to be more appropriate. On the other hand if, as in North America, you wish to provide a split-phase, 240/120-V, single-phase supply in addition to three phase, then you might consider the delta connection to be more appropriate. Neither is 'better'.
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∙ 11y agobelow 10 hp DOL starter r used & above10 Hp star delta is used. Star delta contain three contractor ,one relay ,and timer for switching star to delta connection.It has two wring power & control.
for circuit diagram mail at assasinchange@gmail.com.
Star -delta is a starting method that enables the motor to start running slowly in star and progressively gains speed when it is switched to delta.
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∙ 11y agostar connection is used to reduce phase voltage and 3phase 4wire system
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∙ 9y agofor example in Transformers, the star connection will connect the earth without any extra instrument and it will limit current of third harmonics.
best regards
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∙ 11y agostar/starconnections are not delta
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Why is star connection used in a three phase transformer?
The power of all three phases can be transmitted on three conductors.A star connection, as opposed to a delta, provides a grounding reference. Also, for ground faults on the secondary (assuming no delta third winding, or source third winding) will be a direct ratio similar to phase faults, instead of 57%. Another reason is to avoid the inherent phase shift involved in a delta/star configured transformer.Another AnswerA 'star-connected' secondary is the standard European connection for a three-phase distribution transformer, as it provides a line voltage of 400 V together with a phase voltage (i.e. line to neutral) of 230 V.
What is the difference between star delta and wye delta?
With a delta connection, picture a triangle. Each side of the triangle is a transformer or motor winding. Call the 3 corners of the triangle A, B, and C. There are only 3 wires except for a safety ground, which has no connection to, nor is any part of, the power transmission service lines.but for the star connection take our triangle above and use your wire cutters (literally) to cut the triangle apart at the corners. rearrange the three sides (transformer or motor windings) to form a Y. Where the three sides join in the centre, connect a fourth wire. Call this wire "neutral". Call the three ends A, B, and C. Connect the 3 supply service lines to A, B, and C.
When is a motor in star or delta connection?
Star (or wye) connection is where each of the three phases has a fourth conductor, neutral, as its current return. Current flow in this configuration is phase to neutral, which is also grounded back at the distribution center. There will be five total connections, phase A, B, and C, neutral, and (protective earth) ground. Delta connection is where each of the three phases uses the prior phase as its current return. Current flow in this configuration is phase to phase, and there is no neutral, though there is still a ground. There will be four total connections, phase A, B, and C, and (protective earth) ground.
Why vector group is required?
There are various ways in which you can connect a three-phase transformer's primary and secondary windings, or in which you can connect three single-phase transformers to create a three-phase transformer bank. For example: wye-wye, wye-delta, delta-delta, delta-wye, etc.For each connection, there is a natural phase shift between the primary and secondary line voltages. This is called the angular displacement (or 'phase displacement') of the transformer connection.If you wish to parallel two three-phase transformers, or two three-phase transformer banks, then their angular displacements must be the same (there are also other requirements not relevant to this answer).A vector group is a method of specifying a three-phase transformer (or transformer bank) method of connection and its angular displacement. Transformer connections from the same group can be paralleled. Those in different groups cannot
What type of star is Delta?
Delta Scuti is a giant star. It is part of the Scutum constellation. It is also known as a variable star because its brightness as seen from earth fluctuates.
When was Delta Connection - Kenya - created?
The delta connection was founded in 1984 this was one of the four main skyteam. Also delta connection was founded to have middle population community. Also known as feeder flights.
What happens when a phase gets short and also when it get opened in a delta and star connection?
In star connection when two phase is short,it work as single phase system. In delta when one phase is open ,it work as a single phase.
Why does delta connection have no neutral connection?
Lets compare between a star and delta connection in 3-phase power types. In a star connection, there are 6 connections (A1, B1 and C1 being the outer arms of the 3 armed star and at the centre, A2, B2 and C2). The center is called the neutral or star point which carries out the any unbalanced current loads through its connection. That is why if you lose out the neutral point in a star connection, there will be an overflow of current through to the loads. The loads also take in more current, generating much more power and could damage the appliance you are using and the components the line current is connected to, since excess heat and overworking may result.In a delta connection, the connection has only 3 and on a piece of paper it is sketched as the connections being joined arm to arm. One side is A phase, B phase and C phase. Getting to the point, a Delta connection does not have a earth wire because the live voltage is always the same throughout the connection. Since phase and line voltage are the same and constants. It also means the line current will change without affecting other components within the circuit. Balanced Delta connected circuits or loads can only have their power supply sourced from a star connection and a balanced Star load can only have their voltage supply come from a delta connection.Another AnswerWith a delta connection, the phasor sum of the three line currents is zero, whether the load is balanced or unbalanced, so no neutral is necessary.
Halo 2 delta halo?
If you are talking about the Halo ring in Halo 2, it would be Installation 05, also called Delta halo.
Why is process of finding a first derivative called differentiation?
When finding the first derivative, you calculate the slope of the curve at a point by determining the ratio of delta y over delta x. You make delta x and delta y smaller and smaller; in fact, you take the limit of delta y over delta x as delta x goes to zero.At this zero limit point, delta y is called dy, and delta x is called dx. They are also called differentials, hence the term differential calculus. They represent the rate at which x and y change at various x's and y's.Since we are working with differentials, the process of determining the slope, also known as the first derivative, is call differentiation.
Why is star connection used in a three phase transformer?
The power of all three phases can be transmitted on three conductors.A star connection, as opposed to a delta, provides a grounding reference. Also, for ground faults on the secondary (assuming no delta third winding, or source third winding) will be a direct ratio similar to phase faults, instead of 57%. Another reason is to avoid the inherent phase shift involved in a delta/star configured transformer.Another AnswerA 'star-connected' secondary is the standard European connection for a three-phase distribution transformer, as it provides a line voltage of 400 V together with a phase voltage (i.e. line to neutral) of 230 V.
What is the land formed at the mouth of a river called that is deposited by silt?
The land formed by deposited soil at the mouth of a river is called a delta (named for the Greek letter, which is similarly triangular in shape).The most well known are the Ganges River Delta, India, the Nile River Delta, Egypt, and the largest is the Amazon River Delta, Brazil.
What is the widest part of a river called?
It's called an estuary, or in Scotland, a firth. Where it spreads out into a muddy triangle, it's called a delta.
What is the soil deposited by rivers called?
The soil or sediments itself is called silt, and the landform that is often created at the mouths of rivers is called a river delta. Sand bars are also created in rivers and other waterways by deposited silt.
What is large body of fresh water called?
There is no general term for the connection between a lake and the ocean that it is an arm of. The area where a river or stream enters the ocean is a mouth, also possibly a delta or an estuary.
What term is used for the triangular-shaped deposit of sediment sometime found at the mouth of a river?
An alluvial plain, sometimes also referred to as a fluvial plain.
What is another name for an arrowhead shape?
An arrowhead can also be called a deltoid or a delta (either will do)!! hope this helps!!
