Why disc insulators grooved at bottom?  

1 Answer

Answer :

To increase the creepage distance, reduce the chances of flash over.  

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Description : The motor starts when the start button in the illustration is pushed, but stops when the button is released the trouble is _________. EL-0007 A. the incorrect thermal overload coil B. a faulty 'M' coil C. a dirty contact on the Disc.Sw. at 'L3' D. a faulty holding relay contact

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Description : The operating torque of the upper induction disc-type element, or timer element, of an AC reverse power relay is obtained from ____________. A. the main bus B. a separate battery source C. line voltage D. electromagnets

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Description : If the illustrated motor fails to start and gives a loud hum when the start button is pushed, the problem is ________. EL-0007 A. one of the phases to the motor is not energized because of ... electrical distribution system D. 'OL1' is open because of 'T1' overload causing the motor to single phase

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Description : What is more important insulators or conductors?

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Description : What is more important conductors or insulators?

Last Answer : Conductors and Insulators. In a conductor, electric current can flow freely, in an insulator it cannot. Metals such as copper typify conductors, while most non-metallic solids are said to be good insulators, having extremely high resistance to the flow of charge through them.

Description : Are perspex and polythene conductors r insulators?

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Description : What are Liquid insulators and examples?

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Description : What is more important conductors or insulators?

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Description : This group of alumino-silicate minerals is widely used in making electrical insulators (1) Bauxite (2) Chrornite (3) Manganese (4) Mica

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Description : Superconductors are those elements – (1) Whose conductivity is intermediate between metals and insulators (2) Whose resistance falls almost to zero at very low temperature (3) Which conduct electricity only at super-high temperature (4) Which conduct electricity only, at super-high temperatures

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Description : A bird sitting on a high tension electric wire does not get electrocuted because – (1) it has high resistance (2) the body is earthed (3) it does not form a closed path for the flow of current (4) its feet are good insulators

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