Answer / 7anoter4

If the change in load will be the same Pa1=Pa2 and the
rated frequency fo1=fo2

for the same time interval dt1=dt2

IF Pa=H*MVA/180/fo*d2R/dt2 [See IEEE-399 ch. 8.6.2 How
stability programs work]

and d2R/dt2=2*pi()*df/dt

then (df/dt)1=Pa/2/pi()*180*fo/MVA1/H1 and

(df/dt)2=Pa/2/pi()*180*fo/MVA2/H2

(df/dt)2/(df/dt)1=MVA1*H1/MVA2*H2

If MVA1=MVA2 then (df/dt)2=(df/dt)1*H1/H2

df2=12*30/42=8.57 Hz

There is air in a room . the top and bottom of the room are at constant temp. T1 and T2. DRAW THE temp profiles if a. T1 greater than T2 b. T1 less than T2

0 Answers  

---

Why back emf used for a dc motor? Highlight its significance.

0 Answers  

---

I want to apply for ONGC recruitment 2012 .I am BE Electrical but it is mentioned that to apply for this post you have to have Electrical supervisor certificate .so please tell me from where can i get such certificate ???

1 Answers  

---

mccb service sittings be done?

0 Answers  

---

Brief function of stepper motor

1 Answers  

---

why the admittance matrix or y bus matrix of a large network is called sparse matrix?

3 Answers  

---

DIFFERENCE B/W NEUTRAL AND EARTH?

2 Answers   Genesis, IBC,

---

What are linear and non-linear systems?

0 Answers  

---

will a bulb glow connected to two phases of a delta connection?

6 Answers  

---

how work the lighting arrestor?

2 Answers  

---

Is it possible to measure correct value of earth resistance & cable insulation ristance with out disconncting earth lead & both sides of cable ends? If not, any other method to measure ER & CIR with out disconneting from the system.

0 Answers   HAL,

---

WAHAT IS ELECTRICITY

5 Answers   Vijai Electricals,

---