Answer / mahavir jagdev

The petrochemical industry is susceptible to fire hazards. In DC motors the carbon brushes on the rotor create sparks, which can ignite the petro fumes or vapours. The AC motor speed can be controlled with electronic speed controllers (frequency or voltage type) thus the danger of fire is not there. Even in olden days the coal and other mines which had ignitable gases, had fire proof DC motors and switch gear, which was expensive.

whow we find out dc motor field aur armature resistance

1 Answers  

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What is the function of an Auto reclosure relay. How does it work??

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A 11 KV motor is working. if the supplay is fail. what will happened with it's breaker? Trip / remain the same condition?

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what is the diffrence between R Y B phase and why it is called RYB

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why we are using the 2 slope in differential relay?but in busbar differential we are using only one slope. what is the reason.

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Distinguish between shunt and series field coil constructions.

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what is battery impedance testing and how we perform this test with four wires.

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why semicondoctor use in HT cable?

1 Answers  

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