MGVCL Exam Paper (30-07-2021 Shift 2)
Consider the following statements associated with Buchholz's relays. Statement 1: Buchholz's relay is a current operated device. Statement 2 : Buchholz's relay is placed between the transformer tank and the conservator.
Buchholz relay is gas operated relay. It will operate when internal fault occurs in transformer. It is placed between tank to main conservator. It has two contacts trip and alarm. Use of Buchholz relay in distribution transformer is not economical.
A term brown out means it is an intentional or unintentional drop in voltage in an electrical power supply system. Brown outs are long-term (hours-long) voltage sags caused by system overload. Deviations from the regular sinusoidal wave, both on the utility side and on the customer side, result in poor power quality.
Equivalent resistance of the circuit, Req = (12||18) + 8 Req = 7.2 + 8 Req = 15.2 ohm Source current = current through 8 ohm resistor, I = Vr/R8 I = 20/8 I = 2.5 A Supply votage V = I*Req V = 2.5*15.2 V = 38 V
Where, Pmp is maximum power in watt Vmp maximum voltage at maximum power in volt Imp is maximum current at maximum power in ampere Voc open circuit voltage in volt Isc is short circuit current in ampere
Fill Factor = Pmp/(Vosc*Isc) = (Vmp*Imp)/(Voc*Isc) = (2.65*0.5)/(0.7*3) = 0.63
EXAMIANS