Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The volt-ampere euation for a long-shunt compound motor is given by Vt = Ea + Ia(ra + rs) Vt= Ea– Iara Vt = Ea + Iara+ ILrs Vt= Ea + Iara Vt = Ea + Ia(ra + rs) Vt= Ea– Iara Vt = Ea + Iara+ ILrs Vt= Ea + Iara ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The frame of an induction motor is made of stainless steel. silicon steel. closed grained cast iron. aluminium. stainless steel. silicon steel. closed grained cast iron. aluminium. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following load normally needs starting torque more than rated torque? Centrifugal pumps. Conveyers. Blowers. Air compressors. Centrifugal pumps. Conveyers. Blowers. Air compressors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 100 KVA transformer is operating at 60 Hz, 240 V supply. The same transformer is operating at 50 Hz, 200 V supply. The new rating is 50 KVA 100 KVA 83.33 KVA 123.3 KVA 50 KVA 100 KVA 83.33 KVA 123.3 KVA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The voltmeter connected across a generator reads voltage same at no load and at full load (rated). The generator is of the type shunt generator. level compound. short - shunt generator. series generator. shunt generator. level compound. short - shunt generator. series generator. ANSWER DOWNLOAD EXAMIANS APP