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They all have delta primaries and star secondaries, possibly earthed. The number is the angle of the secondary voltage's lag behind the primary's, expressed as an hour on a clock-face.
11 --> Secondary leads primary by 30 degrees
1 --> Secondary lags primary by 30 degrees
5 --> Secondary lags primary by 150 degrees, making the red secondary voltage lag the yellow primary by 30 degrees (using UK Red/Yellow/Blue phases)
Dyn11 and Dyn1 are much more common than DYn5
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How can you test ZNyn11 Vector group transformer?
This vector group test is done to confirm whether the vector group provided in the name plate is correct or not and also to confirm that the winding has not been damaged during transport, installation and erection. Taking a particular example, for Dyn11 transformer we have to apply 3~ 400v to the primary, with primary 'U' & secondary 'u' shorted.... then check the voltage across different terminals such as V-v, V-w, W-w, W-v for Dyn11 configuration (V-v = V-w = W-w)less than W-v.... you can compare the results after drawing the vector diagram for the same...... the purpose of shorting the primary U & secondary u is to nullify the phase shift, to obtain a reference vector...
Why there is a phase shift of 30degree in Dyn11 3 phase transformer?
The phase shift is caused by inductance in the transformer. Any inductance from magnetic flux that fails to link both windings is called leakage flux, and the resulting inductance is called leakage inductance.
How can you test the vector group DYn11 and vector diagram?
connect the neutral point of the star (secondary) to u phase of primary, and now apply voltage to primary and measure the voltage between V&R, W&B, V&Y and V&B. when you measure voltage b/w 1. V&R the voltage must be maximum, 2. W&B Should be minimum and 3. voltage between V&Y and V&B should be same U.V&W are primary (Delta) R,Y&B are secondary (Star)
How to parallel the Dyn1 and Dyn11 Transformer?
you keep the hv & lv on the dyn11 tx straight in phasing. you then put a cross on any two phases on the hv side of the dyn1 tx, and do the same cross with the phases on the lv side of the tx. for instance lets say we cross a & c phases on the hv & lv sides of the dyn1 tx. now draw a diagram with the four tx, split them up, 2 x dyn1, 2 x dyn11. now on the diagram where you have dyn1 tx, change the the phase plates to read cba left to right, also change the lv side to match. leave the phase plates on the dyn11 tx alone to read abc left to right on both sides. now draw the cables going between them on the hv & lv sides. now if a phase always goes to a phase and b & c phases do the same it will all tie in. prove it to yourself and follow a phase threw all the tx's, do the same will b & c phases. I do it all the time at my job, works every time.
How change Dyn11 to Dyn3?
DYn1 = Delta connected highside winding, Wye connected lowside winding, neutral brought out, lowside lagging by 30 degrees DYn11 = delta connected highside winding, Wye connected lowside winding, neutral brought out, lowside leading by 30 degrees In a DYn1, the lowside A phase is coupled to the highside A-B leg. In a DYn11, the lowside A phase is coupled to the highside C-A leg. So to convert one to another, you must physically change this coupling, which would require rewiring the internal connections of the transfomer delta.
What is the difference betbeen Dyn11 and Dyn1?
The key difference between Dyn11 and Dyn1 refers to their vector groups. Dyn11 has a neutral terminal connected to the star point of one of the windings, while Dyn1 does not have this connection. This means that in Dyn11, the neutral terminal is available for grounding or other purposes, which may affect system protection and grounding schemes.
How do you determine the vector grouping of a DYN1 transformer?
The vector grouping of a DYN1 transformer is determined by the relative phase shift between the primary and secondary windings. It is designated based on the clock-hour positions of the HV and LV terminals when the high voltage winding is at 12 o'clock and the low voltage winding is positioned accordingly. The vector group is typically denoted as Dyn1, Dyn5, Dyn11, etc., indicating different phase relationships.
What is the meaning of DY 11 on a transformer nameplate?
there is no specification of Dy11.. it will be Dyn11.. it is the vector group of the transformer. capital d means primary winding is delta secondary winding is star(y) and the secondary current lags voltage by 30degree this angle when shown in clock will be looking like 11 o clock
How can you test ZNyn11 Vector group transformer?
This vector group test is done to confirm whether the vector group provided in the name plate is correct or not and also to confirm that the winding has not been damaged during transport, installation and erection. Taking a particular example, for Dyn11 transformer we have to apply 3~ 400v to the primary, with primary 'U' & secondary 'u' shorted.... then check the voltage across different terminals such as V-v, V-w, W-w, W-v for Dyn11 configuration (V-v = V-w = W-w)less than W-v.... you can compare the results after drawing the vector diagram for the same...... the purpose of shorting the primary U & secondary u is to nullify the phase shift, to obtain a reference vector...
What is DYN11 of a transformer?
It's a description of the some of the electrical properties of the transformer. This is a Delta connected highside (the D), wye connected lowside (Y) that is grounded (N) and there is a 330 degree phase shift between the highside and the lowside (the low voltage is leading the high voltage by 30 degrees).
Why there is a phase shift of 30degree in Dyn11 3 phase transformer?
The phase shift is caused by inductance in the transformer. Any inductance from magnetic flux that fails to link both windings is called leakage flux, and the resulting inductance is called leakage inductance.
How do you calculation of selecting Neutral Earthing Transformer?
iT IS ISMILAR TO THE GROUND RESITOR CALCULATION FOR TRANSFOMER THE TYPICAL EXAMPLE WAS ANSWERED EARLIER FOR TRANSFORMER DT.19-06-2009 Neutral of transformer can be grounded solidly earthed OR with Neutral Grounded with Resistance. Typical shunt calculations fro 5 MAV 11/6.6 kv transformer neutral are as :_ Transformer rating = 5 MVA Voltage ratio = 11/6.6 KV Vector Group = Dyn11 (6.6 KV ground through Resistor) During Earth fault voltage between Neutral & Earth = 6.6/√3 = 3.81 KV Earth Fault current will be limited to = 5 x 10³ /(√3 x 6.6) = 437.38Amp. N.G.R. value in ohm = V / I = (3.81 x 10³) / 437.38 = 8.71 Ohm Value of N.G.R. is 437.38 Amp, 8.71 Ohm., 10 Sec NGR are inserted On Higher voltage to restrict earth fault current BY SRI
Can a 3-phase DYN 1 transfomer be connected in parallel with a DYN11?
No
How can you test the vector group DYn11 and vector diagram?
connect the neutral point of the star (secondary) to u phase of primary, and now apply voltage to primary and measure the voltage between V&R, W&B, V&Y and V&B. when you measure voltage b/w 1. V&R the voltage must be maximum, 2. W&B Should be minimum and 3. voltage between V&Y and V&B should be same U.V&W are primary (Delta) R,Y&B are secondary (Star)
How to parallel the Dyn1 and Dyn11 Transformer?
you keep the hv & lv on the dyn11 tx straight in phasing. you then put a cross on any two phases on the hv side of the dyn1 tx, and do the same cross with the phases on the lv side of the tx. for instance lets say we cross a & c phases on the hv & lv sides of the dyn1 tx. now draw a diagram with the four tx, split them up, 2 x dyn1, 2 x dyn11. now on the diagram where you have dyn1 tx, change the the phase plates to read cba left to right, also change the lv side to match. leave the phase plates on the dyn11 tx alone to read abc left to right on both sides. now draw the cables going between them on the hv & lv sides. now if a phase always goes to a phase and b & c phases do the same it will all tie in. prove it to yourself and follow a phase threw all the tx's, do the same will b & c phases. I do it all the time at my job, works every time.
How change Dyn11 to Dyn3?
DYn1 = Delta connected highside winding, Wye connected lowside winding, neutral brought out, lowside lagging by 30 degrees DYn11 = delta connected highside winding, Wye connected lowside winding, neutral brought out, lowside leading by 30 degrees In a DYn1, the lowside A phase is coupled to the highside A-B leg. In a DYn11, the lowside A phase is coupled to the highside C-A leg. So to convert one to another, you must physically change this coupling, which would require rewiring the internal connections of the transfomer delta.
What is the difference between Dyn-11 and Ynd-11?
Dyn-11 refers to a transformer connection where the neutral terminal is not connected to the ground. Ynd-11 refers to a transformer connection where the neutral terminal is connected to the ground. Thus, the key difference lies in how the neutral terminal is treated in each connection scheme.
