Answer / sumit

in absence of 3 phase supply no rotating magneic field will
produce . . .. . .

Answer / kj

A 3 phase supply is the lowest number of phases where a
rotating field is produced. No extra starting controls are
needed (e.g. capacitor start or start windings)
Two phase systems have been used and can produce a rotating
field but it has to use a setup with separate neutrals for
each of the 2 phase. It therefore requires 4 wires to each
motor instead of 3 and it is also not as efficient.
Three phases also has the advantage of the currents in the
nuetral not being the sum of the 3 phase currents. In that
way only a single neutral can be used as the return for any
single phase load on all the 3 phases.

Answer / t lakshmi narayana

Why because two phase supply cannot work.Let us consider 2
phase a,b.If a=0 then b=180 electrical degrees apart. Both
are out of phase i.e net torque is equal to zero.
Electrical degree = 360/phases.
In 2 phase it is 180
In 3 phase it is 120 which gives a torque.

Answer / wareagle

Because it does not exist.

How equivalent impedance is calculated in thevenin theorem?

0 Answers  

---

how much test voltage should applied for tan delta test.

2 Answers   Electrical, TATA,

---

What is FTA card? How it works?

0 Answers  

---

lllg,llg,ll,lg,lll which fault is severe and why?

10 Answers   COEP, GE, PSC,

---

What is the function of turbo charger in generators

1 Answers  

---

---

why do we prefer alternating current in india where as in USA prefers DC?

3 Answers   Bhel, GMR, Texmo,

---

how we check vector group dyn7

1 Answers  

---

Why are the voltage levels in a powersystem are 11KV,33KV etc., why not 10KV,30KV?

2 Answers  

---

How does the phase sequence controller works, how it identifies the phases? confirm working principle

0 Answers  

---

What happen to the transformer if the OLTC frequently used for lower and raise occured 50times daily?

0 Answers  

---

Difference between single phase and three phase?

1 Answers  

---

hi, i finished b.tech eee in 2008, im worked in dg sets mfg company , now i left job in 6months back, now again i want get job core side, how can i get? is there any couses we have learn to get better oppurtunity? /

0 Answers  

---