Answer / gajendran.al

Variation in supply voltage to motor affects the torque
produced by the motor and is not affected much with +/- 10%
whereas variation in frequency affects the speed of the
motor. Even 1Hz variation could vary speed by 30 rpm for a
4 pole motor. So variation in frequency is not advisable in
motor
Pl note that increase in supply frequency makes the motor
rotate above rated speed which may cause mechanical failure
of motor.

Answer / subash

But in motors the rated frequence +or- 5% will be there its
true

Answer / shriram.....

For the motor we are not using ups power supply

In ups power supply, we can maintain the voltage as well as
frequency.

But we are using raw power for motors in plants.

Eg if I we are using some load. Now I getting 415 volts at
full load if I reduce some load any reasons then voltage
will lightly increase so voltage will not stay constant.

For that reasons operating voltage +/- 10 %

Shriram....

What are the difference between these terms ? e.m.f, voltage, potential, potential difference, current etc? what are the difference between these terms ? (electromotive force) e.m.f, voltage, potential, potential difference, reference potential, reference potential difference, current. How can i explain and describe these all terms in single line each and little more explaination too thanks

2 Answers   Siemens,

---

star delta starter contorl circuit... drawing..

0 Answers  

---

What is rated value? is it phase values or line values?

1 Answers  

---

TYPE'S OF BREKAR ,WHAT IS TRANSFORMAR & SAFTY. STARTER DOL & STAR DELTA STARTER.

0 Answers   Amtek,

---

where we use zero sequence current transformer or core balancing ct.

2 Answers  

---

For a 6.6kV Motor it is recommended to do megger test with 500 V d.c and not more than 5kV d.c but the Hi voltage withstand test should be performed by 12kV AC. Why the dc voltage test should be limited but AC voltage withstand test could be with such a high voltage?

0 Answers   Hormozgan Steel,

---

What is the one main difference between ups & inverter ? And electrical engineering & electronics engineering ?

0 Answers  

---

What is the difference between a Root Locus plot and a Bode plot?

0 Answers   GE,

---

how much watts are equal to one unit of energy meter?

9 Answers  

---

what is the difference between power transformer & distribution transformer and what are their ratings respectively?

4 Answers  

---

pls tell us AC plant are how do work and parts name with picture

0 Answers   Mukand,

---

What is the fuction of surge arrester and surge suppressor? Modern days line designes are based on which surge?

1 Answers  

---