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What are the problems associated with the Y-Y three phase transformer connection?
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∙ 7y ago
Your third leg is called the high leg and can exceed 180 or more volts. In a 3 phase panel you will loose a third of your circuits unless they are used for motors or other equipment that uses three phase evenly through its function {meaning it doesn't use one leg exclusively for controls or 110V functions. It get a bit involved explaining the windings of a transformer and center taps but suffice it to say one leg gets more than it's share of windings in the transformer. It was used in the early years of industry when single phase 240V systems were the only game in town and they wanted to get more power from the Wye set up prior to delta. It never was popular but a necessity for industry and grew only because of slow development incorporating the 208V delta 3 phase system.
Edyth Anderson
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What is the advantage of an open delta transformer?
An open-delta connection is a method of providing a three-phase supply, using two single-phase transformers. It is particularly useful if , say, one single-phase transformer, part of a three single-phase transformers forming a three-phase transformer bank, becomes damaged -allowing the two remaining transformers to provide a temporary three-phase supply to the load. The drawback with this connection is that the capacity of the transformer bank is reduced, and it can only provide a lower load current.
In a 3-phase high voltage star-star connection 140KVA transformer and load phase voltage is 115v and frequency is 400hz what is the total load current?
Maximum load current on a 140KVA, three phase transformer when the output voltage is 115 v phase to phase is: 140kva / sqrt (3) / 115 = 703 Amps. frequency does not matter here.
What is Zigzag Transformers?
A zigzag transformer is used in connection with 3 phase and is made up of 6 coils connected in a "Y" manner. Each leg of the "Y" is made up of a coil on a different phase leg of the transformer. The neutral formed by the zigzag connection is very stable. Therefore, this type of transformer, or in some cases an auto transformer, lends itself very well for establishing a neutral for an ungrounded 3 phase system. Many times this type of transformer or auto transformer, lends itself very well for establishing a neutral for an ungrounded 3 phase system. Many times this type of transformer or auto transformer will carry a fairly large rating, yet physically be relatively small. This particularly applies in connection with grounding applications. The reason for this small size in relation to the nameplate KVA rating is due to the fact that many types of grounding auto transformers are rated for 2 seconds. This is based on the time to operate an overcurrent protection device such as a breaker. Zigzag transformers used to be employed to enable size reductions in drive motor systems due to the stable wave form they present. Other means are now more common, such as 6 phase star.
How do you get 380 volt from 220 3 phase?
Only with a 3 phase transformer.
How can you get a 240V single-phase power from a 120V 3-phase service?
First of all there is no common three phase 120 volt service. There is in North America a three wire 120/240 volt single phase service. That being said, if you want to change a 120 volt source to 240 volts it must be done with a transformer. Its classification is a step up transformer. The primary side of the transformer H1 - H2 will be connected to the 120 volts. The secondary side of the transformer X1 - X2 will be connected to the 240 volt load. The transformer is sized by the current required by the 240 volt load.
What are the problems associated with the three-phase transformer connection?
One must check the design of the transformer windings. STAR - Delta or Star to star or Delta - star or Delta Delta. Wiring must be done accordingly.
What is The Connection in three phase transformer?
the connection here meant for the connection of windings in three core or limbs of a transformer. it might be delta or star connected.
Why is the Neutral fundamental in a three phase Y-Y Transformer connection?
Suppression of harmonics
What is the advantage of an open delta transformer?
An open-delta connection is a method of providing a three-phase supply, using two single-phase transformers. It is particularly useful if , say, one single-phase transformer, part of a three single-phase transformers forming a three-phase transformer bank, becomes damaged -allowing the two remaining transformers to provide a temporary three-phase supply to the load. The drawback with this connection is that the capacity of the transformer bank is reduced, and it can only provide a lower load current.
Is there a neutral on a three phase transformer?
It depends on whether you are wye or delta connected. A transformer is a transformer, and a three phase transformer is simply three transformers. The key is in how you hook them up.AnswerIt depends on how the transformer is connected. If one set of windings is connected in star (or wye), then the star point is/canbe earthed and becomes the neutral for that particular connection; this is the standard connection for the secondary (low-voltage) of European distribution transformers. In North American three-phase distribution transformers, the secondary windings are connected in delta, and one phase is centre tapped, earthed, and that becomes the neutral point for a 240/120-V split-phase supply to a residence.This answer applies to both three-phase transformers, and to single-phase transformers which have been connected to form a three-phase transformer bank. (It is incorrect to say that a three-phase transformer is simply three single-phase transformers!)
What is the voltage phase shift between primary and secondary line voltages in star-delta transformer connection?
The voltage phase shift between primary and secondary connections in a transformer is 180 electrical degrees.
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 is the xo terminal on a transformer used for?
The XO denotes the joined secondary terminal connection of three single coils of a three phase transformer. It is the common return on any unbalanced current of a three phase system.
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.
Star-star connection of transformer?
Star Star TransformerStar Star Transformer is formed in a 3 phase transformer by connecting one terminal of each phase of individual side, together. The common terminal is indicated by suffix 1 in the figure below. If terminal with suffix 1 in both primary and secondary are used as common terminal, voltages of primary and secondary are in same phase. That is why this connection is called zero degree connection or 0o - connection.If the terminals with suffix 1 is connected together in HV side as common point and the terminals with suffix 2 in LV side are connected together as common point, the voltages in primary and secondary will be in opposite phase. Hence, Star Star Transformer connection is called 180o - Connection, of three phase transformer.Vikram Meena
What is phase shift in three phase transformer?
The phase shift in three-phase transformer from winding of Transformer and determine by vectorgroup of transformer such as YNd1 High voltage connect to wye Low Voltage connect to delta so L.V. lag H.V 30 degree.Answer'Phase shift' or, more accurately, 'angular displacement', is the angle between the secondary line voltages and primary line voltages of a three-phase transformer.
What electrical phase does H1 denote?
H1 is a terminal designation on the primary side of a transformer. The counter part to this terminal is H2. These two terminals are the connection points for the primary coil of the transformer.
