Answer / k.prakashchandra

EFR is for general earth fault and REFR is for earth fault
within the area covered or for a certain equipment e.g.
tranformer.

Answer / nur.asidik

EF/SEF/50N/51N/51G can be detected by core balance CT or by vector summation of line CT(residual)
64REF is by comparing current flowing at TR neutral CT with residual CT at line CT,

Answer / harnish desai

REF will detect earth fault within its equipoment & work on
principal of vector sum of Ir + Iy + Ib + In = 0.
Ef relay will sense current in only neutral CT & operate
relay.

what is Ith current?

4 Answers  

---

what type of earthing is done on hilly rocks.

4 Answers  

---

tell me some type of questions throught which i can prepare for exam and do my best

0 Answers   Jindal,

---

diff. between star, delta connection?

4 Answers  

---

if a 3phase 100kva distribution transformer , 400 v,50 hz, 4-wire system is loaded at 160 k.w mostly 1-phase Lighting & Airconditioning split a.c load what will be the net effect on the power system in terms of voltage, powerfactor, current , efficiency of xformer

0 Answers  

---

What is the power requirement of tamil nadu for one month?

0 Answers  

---

what is the operation of UPS ? can any one answer me?

7 Answers  

---

Which one is more accurate servo or stepper motor and why?

2 Answers   BARC, HPT,

---

Define magnetic centre in a motor?

1 Answers  

---

if field winding of synchronous generator are shorted on each other will it start or burn or run for short time like induction motor

1 Answers  

---

what is the use of cable in our environment ?

0 Answers  

---

I am a electrical engg. diploma holder,applied for junior engineer (electrical),Kolkata RRB. Have I to attend all electrical,mechanical&civil portion in written exam.???

0 Answers   RRB,

---