Answer Posted / devidas
First symbol/symbols, capital letters: HV winding connection.
Second symbol/symbols, small letters: LV winding connection.
Third symbol, number: Phase displacement expressed as the
clock hour number.
Winding connection designations
High Voltage Always capital letters
Delta - D
Star - S
Interconnected star - Z
Neutral brought out - N
Low voltage Always small letters
Delta - d
Star - s
Interconnected star - z
Neutral brought out - n
Phase displacement
Phase rotation is always anti-clockwise. (international
adopted convention)
Use the hour indicator as the indicating phase displacement
angle. Because there are 12 hours on a clock, and a circle
consists out of 360°, each hour represents 30°.
Thus 1 = 30°, 2 = 60°, 3 = 90°, 6 = 180° and 12 = 0° or 360°.
The minute hand is set on 12 o'clock and replaces the line
to neutral voltage (sometimes imaginary) of the HV winding.
This position is always the reference point.
Because rotation is anti-clockwise, 1 = 30° lagging (LV lags
HV with 30°)and 11 = 330° lagging or 30° leading (LV leads
HV with 30°)
To summarise:
Dyn11
Delta connected HV winding, star connected LV winding with
neutral brought out, LV is leading HV with 30°
| Is This Answer Correct ? | 302 Yes | 15 No |
Post New Answer View All Answers
Sir,In our company there are 3 caterpillar make(capacity:(1) 3.3KV,2.5MW(2)3.3KV,2.5MW & (3)3.3KV,1.9MW) & 1 deutz make (capacity:11KV,3.8MW)gas engines utilised,all are running in paralell. There are three transformer utilised,(1) 6.25MVA,3.3KV/22KV,Impedence voltage:6.7% used for two generator,both are 2.5MW(2)5.5MVA,3.3KV/22KV,Impedence voltage:7.2% used for one generator of 2.5MW & (3) 5.5MVA,11KV/22KV,Impedence voltage:7.8% used for one generator of 2.5MW.all generator breakers capacity of 1250Amps. Sir,I want the details of fault level calculation of generator,transformer individually & for whole system. If you require any information from me.feel free for contact me sir.pl.send the answer of my question as the earliest as possible.
Why the unit sizes of hydro generating machines are not standardized as in case of thermal powerplants?
which protection used in power plant?
What is the difference between solid grounding and impedance grounding?
What is the basis for framing the rules of block diagram reduction technique?
What is s-domain and its significance?
what is the use of vcb & isolator in substation?
my bachelors was done with EEE now i got admit in NU with CS as course. how to answer this qns 1) why u choose cs? 2) why u changed from eee to cs
How may I enrol or get admission to your program?
how rectifier transformer work in electroststic precipetatore(esp?
Either the Armoured Earthing strip of HT 3 core cable have to pass through CB CT or not , why ???
In a tap changing transformer where is the tap connected, is it connected in the primary side or secondary side?
what is your aim
hr round
distribution transformer de-rating formula on over limit iron losses