Answer / gogarlatatarao

Basically starter is used for purpose of limiting the starting current ther by it protect the equipment ( motor and generator)from high current , thus the windings of equipment are protected.
 
If no starter is used then the starting current will be huge which damage winding.
            I.e  v=ir, 
                    I= v/r
                    I=220/0.2 
                    I=1100Amp. which is dangerously high  

Where as in case of transformer to protect it from high inrush currents the windings are mechanically braced to with stand these forces.
That's way no starter is used.

                    AND 
Starter is used where breaking and starting operations occurred mostly.
     But if once we start the transformer we can't break it until any abnormal condition occurred.

Answer / pritish

first of all, starter is used to limit the starting current to a safe value. starter is used in rotating machines. in case of transformer, to protect the winding from high inrush current, the insulation is placed in the winding in a manner called, insulation grading. in this method, the two end terminals are placed with high graded insulation and the grading of insulation goes decreasing when we travel from end to middle of the winding. this is done because, in a transient period, the high current first links to the end terminal and then it comes to the middle terminal. as the time constant of transient is 5time constant, between that interval the high current would have vanished. hence no starter is used in transformer instead, insulation grading is used to protect it from surges.

why core is useful for the transformer and in its operation

1 Answers  

---

how calculation to be done of cable size/o.h. conductor size of 11kv h.t.for the load of 2175 kw

1 Answers   Shell,

---

what is power factor

7 Answers   Eskom,

---

I have 380.KVA DG set how to Calculate the units from DG.

2 Answers   Ozone Pharma, Sperry Plast Limited, Sterling,

---

what is called inrush current??

1 Answers   KSEB,

---

Why the dc voltage drop during starting of emergency lube oil pump? The Voltage drop from 135kv to 125 kv for one min. before re-establish to 135kv?

0 Answers  

---

differentiate between one way two gang switch & two way one gang switch, used in designing the loads of building.

1 Answers  

---

Explain What will happen when direction of field current is changed (i.e, field excitation is reversed) in the following machines? 1) Alternator 2) Synchronous Motor 3) D.C Generator ( Shunt or Seies ) 4) D.C Motor ( Shunt or Seies )

3 Answers   NTPC, Transco,

---

What is the function of NGR for the parallel operation of alternator? whats happen when different rating of alternator are running with parallel?

0 Answers   Welspun,

---

what are the safety measures of induction motor?

0 Answers  

---

Swg formulae

0 Answers   Bokaro Steel,

---

how to crack cgpsc,which type of knowledge it is required,where i can get systematic study material and some tips?

1 Answers  

---