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Electrical Engineering β Static Question Bank
π Electrical Engineering Questions
6 questions-
Current transformers are __________________series connected type of instrument transformers
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Why is the transformer core laminated?To reduce eddy current losses. Laminations are thin sheets of steel insulated from each other by varnish. This increases the resistance to circulating eddy currents, minimizing heat and energy loss.
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Which parameters are determined by the Open Circuit (OC) and Short Circuit (SC) tests on a transformer?OC Test: Core loss (Iron loss), Magnetizing reactance (Xm), and Core loss resistance (Rc). Performed on LV side with HV open.
SC Test: Copper loss at full load, Equivalent resistance (Req), and Equivalent leakage reactance (Xeq). Performed on HV side with LV shorted. -
Which parameters are determined by the Open Circuit (OC) and Short Circuit (SC) tests on a transformer?OC Test: Core loss (Iron loss), Magnetizing reactance (Xm), and Core loss resistance (Rc). Performed on LV side with HV open.
SC Test: Copper loss at full load, Equivalent resistance (Req), and Equivalent leakage reactance (Xeq). Performed on HV side with LV shorted. -
Which of the following is not a part of transformer installation?Exciter
Transformer core is generally made of ___________By stacking large number of sheets together
The purpose of the transformer core is to provide ____________Low reluctance path
What is the thickness of laminations used in a transformer?0.1 mm to 0.5 mm
Power transformers other than distribution transformers are generally designed to have maximum efficiency around ______Near full-load
No-load current in the transformer is ____Sinusoidal distorted
Core flux in the transformer is _______________flat-topped
What is the dielectric strength of a transformer oil?35 kV
The insulating material that can withstand the highest temperature safely is _______________Mica
For the parallel operation of two single phase transformers it is necessary that they should have ________same polarity
Transformers operating in parallel mode of operation will share the load depending upon their ___________per unit impedance
What will happen if the transformers working in parallel are not connected with regard to polarity?Incorrect polarity will result in dead short circuit
Why transformers connected in parallel should have same voltage ratio?To avoid no-load circulating current