what is neutral grounding? why is it required? what is
neutral grounding resistor and how is its value calculated??
Answer Posted / minu
@ Pankaj:
"The reason of solid grounding in LV system is that the
amount of earth fault current is very less e.g. for a
single phase to earth fault in a 415V 3 phase system, the
earth fault current is only 240A (considering earthing
resistance 1 Ohm). Whereas in 11kV system, the amount of
fault current will be 6351A. Hence resistance/impedance is
added to reduce the current to a safe value e.g. a 1250 Ohm
resistance in 11kV system limits the fault current to 5A"
i would like to differ in this point of yours. the LG fault
current in a system is never very less. it usually amounts
almost equal to the phase fault current or even more. I can
say this coz i have conducted short circuit studies for many
industrial plants where the LV system is solidly grounded.
Is This Answer Correct ? | 11 Yes | 6 No |
Post New Answer View All Answers
I PURCHASED A DEISEL GENARATOR SET OF AVR TYPE& RATING 125KVA BUT SOME TIMES THE OUTPUT VOLTAGE IS FLUCTUATING WHAT ARE THE PROBABLE REASONS GIVE ME
What is meant by short-pitched winding?
what is resver in electrical enginnering with answer
What is the difference between Droop vs Isoch Control?
I have a drawing of a wound rotor induction motor for a crane. This crane motor has 5 forward speeds & 5 reverse speed implemented of course with different amount of resistance for each speed setting selected. What has got me scratching around is the fact that 8 of the 10 speed selections switch in uneven (unbalanced) amounts of resistances on each of the 3 connections to the motor's rotor.Can this be possible? I would have assumed this would produce unbalanced rotor currents and therefore vibration in the motor. I would greatly appreciate anyone's comments on this. Many thanks, Confused.
How would you calculate power loss in a resistor?
What are the three types of compensators?
what is the purpose of shading ring or shading coil in electrical equipments.
what is the role and fuction of automatic transfer switch in rotary ups
What is the function of attenuator in cro?
Draw the vector diagramme for Asynchronous Induction Generator at noload,half load and fullload.
what is meant by CT`s saturation ? Can we use Metering CT`s with Protetection CT`s ?
Why is a plain induction motor unsuitable for wide speed control?
explain which quantities change in the starting and the and the running condition in induction motor
why output is out of phase in case of common emitter?