Answer the following questions : --------------------------------------------- T
ID: 2989841 • Letter: A
Question
Answer the following questions :
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The voltage designation 7200V/12470VY is used for the primary winding of a single phase distribution transformer. Make the choise below that best fits the above designation.
Question 1 options: Pick ONLY one of them.
1). The winding can be connected between two phases if the feeder line-to-line voltage is 7200 V or it can be connected between a phase and the neutral (ground) if the feeder line-to-line voltage is 12470 V.
2). The winding can operated at a minimum of 7200 V and at a maximum of 12470 V.
3). The winding can be used in multiple connections depending on the feeder voltage (7200 V or 12470 V L-L).
4).The winding can be connected between two phases if the feeder voltage is 7200 V Line-to-Line.
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The power rating of a transformer applies equally to all its windings.
Question 2 options:
True
False
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Power losses in the transformer are due to the following (select all that apply)
Question 3 options: Pick more than one
1).Winding resistance
2).Eddy current loss
3).Hysteresis loss
4).Dielectric loss
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Explanation / Answer
Q1. voltage designation 7200V/12470VY is used for the primary winding.
Here 7200 V, is the voltage between two phases of a feeder. and
12470 V is line voltage in wye connected source, its phase voltage = 12470/ sqrt(3) = 7200 V
so, option (1) is CORRECT. 1). The winding can be connected between two phases if the feeder line-to-line voltage is 7200 V or it can be connected between a phase and the neutral (ground) if the feeder line-to-line voltage is 12470 V.
Q2: TRUE. Power rating of transformer equally distributed among all its phase windings.
Q3: ONLY 1, 2 & 3.
Power losses in a transformer are due to winding resistance, hysterisis and eddy current losses.