Transformers 3-Phase Flashcards

3-phase fundamentals

You may prefer our related Brainscape-certified flashcards:
1
Q

What are the 6 3-phase transformer connections?

A
open-delta/open-delta
open-wye/open-delta
delta/wye
wye/wye
delta/delta
wye/delta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the percentage of AC electricity generated in the world?

A

Almost 95%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many voltages are available on a delta system?

A

Only one voltage between any two wires.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What electrical system is a 3 wire system?

A

A delta system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The line voltage and the phase voltage are the same in a delta system.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The line current and the phase current are different in a delta system by a factor of what?

A

The line current is 1.73 (the square root of 3) times higher than the phase current. The line current on any single line is fed from the two coils that share the same connection as that line. The two phase currents converge at a point to form the line current.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the most commonly used three phase system?

A

The wye or star system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The coils in a wye system share a common point forming a Y. What is the voltage from tip to tip?

A

The tip to tip voltage is called the line voltage which is 1.73 times the phase voltage or coil voltage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many voltages are available on a wye system?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How many wires are on a wye system?

A

A wye system is a 4 wire system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How much can the load be increased by switching a 3-wire delta system to a 4-wire wye system?

A

73%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly