Answer Posted / m raviteja

differential relay is the difference of current from
primary and secondary of the transformer.Normally setting
is at 0.6% if more than that the transformer will tripped
on that relay fault.
the primary current and secondary currents are connected to
individual ct's and that terminals are connected to relay.
differential relay is of two types voltage based and
current based.Normally current based is used in industries.

testing procedure:both primary and secondary currents are
induced to relay and make the required setting if current
difference is more than that the relay acts.

differential relay will not operate when overload the
transformer unless the difference in primary and secondary
currents

what is the use of vcb & isolator in substation?

2358

---

Which contains in POLE ASSEMBLY of a 11KV Kirloskar-make SF6 (Model No-FP620A12)? Will u clarify with drawing?

2152

---

why power not passes in plastic and rubber material

1952

---

how to calculate the Neutral transformer impedance?

2421

---

How can I calculate per unit (KWH) fuel (Gas/ Diesel both) consumption 1MW unit?

2096

---

if flux and load static in dc motor and supply voltage increases 20% then what happened in speed

1891

---

The electromagnetic torque developed is proportional to what in a D.C series motor?

1161

---

Why is the starting current high in dc motor?

1115

---

Match the following a)(X'+Y') b)X'Y' C)XY 1)NAND 2)NOR 3)Carry

1905

---

What is the working principle of MIG welding? and its out put Voltage?

3286

---

What is the meaning of floating point earthing in battery backed systems ?

2004

---

What is the difference between hot and cold loop testing?

1121

---

What if high voltage side circuit breaker of a ehv transformer instead of lvcb? Kindly elaborate.

1730

---

Which cable is use for rtcc control panel

1746

---

What is the basis for framing the rules of block diagram reduction technique?

1507

---