Answer / sabyasachi mishra

If a dc series motor will start with load then its rotor
will rotate at enermous speed .
As we know speed(N) is directly propertional to back emf
(Eb) of motor and inversely propertional to flux generated.
So initially the motor will drawn less or no
current,hence the speed will reach at a dangerious limit.
Hence a dc series motor never started without load.

What shall be the secondary output voltage if the primary winding of a 220/6V, 50 Hz transformer is energized by an 110V, 60 Hz supply?

0 Answers   HPCL,

---

What is the meaning of C1, C61, C91 cable

0 Answers  

---

What is the reason behind current flow(20 A) in amain earth cable of an SMDB? Is cuurent flow(45A etc) through a neutral cable acceptable?

0 Answers  

---

what is mean by harmonics?Type of harmonics?

6 Answers  

---

We have two parts in generator, electrical & mechanical. how it works?

0 Answers   TATA,

---

Why generator field rheostat is set to maximum position and motor field rheostat is set to minimum?

5 Answers   Bhel, College School Exams Tests, TCS, Texas,

---

sigal phase supply is 230 v ac two phase supply is 415 v ac then why three phase supply having supply is 415 v ac why not 690v ac

2 Answers  

---

What is the function of RCCB? What are the different sensitivity ratings & each application?

6 Answers   Wipro,

---

how to modify DOL control panel into Delta Y connection?

0 Answers   ABB, PDCS,

---

please explain power factor in simple words.....

3 Answers  

---

What is voltage

5 Answers   TATA,

---

why in dc generator field rheostate kept in maximum position?

1 Answers  

---