Why restricted earth fault protection is needed? Why can’t differential Protection is sufficient?

1 Answers  

---

why current increases when voltage decreases in ac system

10 Answers  

---

What do you mean by 4.44 in this transformer equetion E=4.44 nfqm

4 Answers   Bharat Bijlee,

---

what is scan time of PLC & in which factor scan time is decide

3 Answers   EEEC,

---

What are the difference between C-Curve and D-Curve for MCB's.

17 Answers   ABB, DLF, Essar, GK companies, Nissi Engineering Solution,

---

---

How can CALCULAT the current carrying capacity of aluminum and cOpper cables respective of that Sq.mm ? with formulas ?

12 Answers   Bajaj, Eagle, Godawari Power and Ispat, Havells, L&T, Mascot, Polycab, SGML, Sterling Wilson,

---

How to calculate the KA rating for a circuit breaker if we know the KVA rating of the generator feeding it?

2 Answers  

---

Why is the starting current high in a DC motor?

2 Answers  

---

during the period of armature reaction ,if the brush shift is not accomplish, what happen?

1 Answers  

---

difference between buscoupler & bussection?

1 Answers  

---

why HV test for cables?.why 0.7times?

1 Answers   Bosch, Prince Food Products,

---

how to choose cable size with respect to load? how to convert cable size in mm2 to sq.mm?

2 Answers   MSL,

---