What is good dielectric break down value for insulating oil?

What is good dielectric break down value for insulating oil?
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1 Answer

Answer :

60 kV.
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The 'dielectric constant' of dry air or a vacuum is _______. A. 1 B. 10 C. 100 D. 1000

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When a megohmmeter is used to test the insulation of a large motor, the initial dip of the pointer toward 'zero' is caused by ____________. A. good insulation B. the capacitance of the windings C. the leakage of the current along the surface of dirty insulation D. the dielectric-absorption effect of the insulation

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When using a megohmmeter to test the dielectric strength of wire insulation, a continuous series of slight downscale kicks by the pointer is result of ____________. A. good insulation B. the leakage of current along the surface of dirty insulation C. the capacitance of the windings D. the dielectric-absorption effect of the insulation

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When a megohmmeter is used to test the dielectric strength of wire insulation, the initial dip of the pointer toward 'zero' is caused by _____________. A. good insulation B. the leakage of current along the surface of dirty insulation C. the capacitance of the circuit D. the dielectric absorption effect of the insulation

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A saturable-core reactor operates on the principle of controlling a load winding's inductance by varying the core's _____________. A. dielectric B. permeability C. reactance D. inductance

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