Answer / adil naseem(pakistan)

wt i think is that 1.1 is form factor and also used in the
transformer equation i.e
E= sqrt(2) * Pi * N * f * Phi

pi=3.14
sqrt(2)=1.414
N=turns
f=50 hz or 60hz frequency
phi=flux

3.14 * 1.414 =4.44
i think due to this factor the voltages are alwas mulitple
of 11. m i corrct????
plz answer if u have better than me???
wd derivatin

Answer / osho katyal

phi= phi max sin wt
d(phi)/dt=phi max cos wt
E=-d N (phi)/dt
E=- phi max cos wt w N
E=- (phi peak/sqrt2) 2 pie f N cos wt
E=-phi peak Sqrt2 pie f N cos wt
E=-4.44 phi peak F N cos wt
- indicates back emf for primary windings,cos wt = 0 at t=o

how u select control transformer for a mccb panels or any panels?for expample we hav 440 volts maim supply and control volts is 230v?

0 Answers  

---

in control panel, how can i measuring the distance between one bus bar to another bus bar. then now only for bus bar. in mpcb and contactor also. that means one mpcb to another mpcb how much distance? how can i calculate that.

0 Answers   ABB,

---

how much capacity(rating) of generator required to operate a load of 100kv.

6 Answers   DSC,

---

Why cannot we insulate HT over head cable to avoid ionization of air around the HT Cable?..By this we can minimise corona loss also..

1 Answers  

---

Is there any thumb rule for cable selection for any current rating ?

1 Answers  

---

132/66kv sub-station procation ?

0 Answers  

---

what are the types of Distribution transformer vector group please explain

7 Answers  

---

Can anyone explain how the vector diagram of a transformer which doesn't have name plate be found whether it is Dy11/Dy5/Yd11 and so on?

4 Answers   TATA,

---

Relation between Sq.mm of wire and Its current carrying capacity?

5 Answers  

---

What are the solutions for avioding sulfide formation at bimetalic (Copper &Aluminium)overhead joints?

2 Answers   HAL,

---

with help of neat sketch explain principle of TIG welding process

0 Answers  

---

What is DPR relay, And what for??

2 Answers   Engro,

---