MGVCL Exam Paper (30-07-2021 Shift 2)
A given solar cell has the following specifications: Open-circuit voltage, Voc: 0.7 V Short-circuit current, Isc: 3 A Voltage at maximum power, Vmp: 0.5 V Current at maximum power, Imp : 2.65 A Calculate the fill factor.
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
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
Class B trip curve : The MCB with class B trip characteristics trips instantaneously when the current flowing through it reaches between 3 to 5 times rated current. These MCBs are suitable for cable protection.
Class C trip curve: MCB with class C trip characteristics trips instantaneously when the current flowing through it reaches between 5 to 10 times the rated current. Suitable Domestic and residential applications and electromagnetic starting loads with medium starting currents.
Class D trip curve: MCB with class D trip characteristics trips instantaneously when the current flowing through it reaches between Above 10 (excluding 10) to 20 times the rated current. Suitable for inductive and motor loads with high starting currents.
Class K trip curve: MCB with class K trip characteristics trips instantaneously when the current flowing through it reaches between 8 to 12 times the rated current. Suitable for inductive and motor loads with high inrush currents.