Answer / satya narayan dutta

no power specification is limited for double earthing.Doube
earthing is required all medium and high voltage
installation.

Answer / prabhakaran

Double earthing is provided for critical equipments like transformer and generator were the earthing is essential. when one earth connection is correded or ineffective the other one will provide the connection to earth. if only one earth connection is provided if connection is not good the system become undgrounded.

Answer / dhamim

double earth is used to given minimum resistance to the flow of whole current of that apparatus in case short circuit or leakage or any other such fault happens  

Answer / venu sumie

If One Earth Connection is failed, another one will work.EX- at the single phase transformer earth failed,transformer produce high voltage nearly 650 volts instead of 240 volts. it is so dangerous ,even though we plug the battery charger at home we get massive shock.hence the transformers should be double earthed.

Answer / vatsal

As per Indian Standard (IS)3043-1987, it is recommended to use double earthing for medium voltages. Medium voltages are as high as 650V (but should not be lower than 250V). So in case of single phase, it will be usual to have single earthing and for 3 phase it is recommended to have double earthing.

Answer / atvk charyulu

refer IS:3043-1987

Answer / ravindra dikshit

Usually, wherever 3 phase supply is used, should have double earthing.

Answer / k.prakashchandra

I think that IE rules insist on 'two distinct earth connections'

Answer / sagarika

can any1 tell me y is double earthing reqd?

Answer / k.prakashchandra

And it is ensure the earth connection if one of the two is
severed.

what is the reason for indication of light in the earth lamps of main switchboard.if there is an earth why does one lamp get dim and the other two bright.

0 Answers  

How transformer winding & oil gets heat.

3 Answers  

how to decide the capacity of accl

0 Answers  

If we use 250A MCCB as a incomer in Control panel for a fault level of 50kA for one second ,assuming temperature rise from 85 Deg. to 100 Deg , Then what will be the Aluminium Bus-bar size for 250A MCCB? Explain in detail.

0 Answers   Usha Capacitors,

what is difference between 5A and 100A CT constructional wise and operation?

1 Answers  

i want to know how to calculate the battery capacity based on the UPS . ex i want to run have one kva UPS Which should run 10 hours ? in that case how many batteries to be installed and what will be the AH Value .

2 Answers  

why there is no current in the rotor body althrough the flux linking with it also get changes. why current only flows in windinds not in rotor

1 Answers   Vedanta,

11. As per the theory current doesn’t flows in Neutral, but practically it is not applicable, explain why? 12. How to take the Vector Group Test in Transformer? What is the purpose of doing Vector Group Test? 13. Why the transmission lines are in 11kV, 22kV, 33kv, and why not 10kV, 20kV, 30kV? 14. Why do we generate 3 Phase AC Supply? It is possible to generate 4 Phase and 5 Phase explain it? 15. Explain why the Voltage drop will happen in 3 Phase line? 16. What is the equipment used to control the generator output? 17. What are the factors to be considered during the Synchronization? 18. What should be value of Circuit breaker operating time and tripping time? 19. Why the CT Secondary is rated as 5A generally? 20. At which time Synchronous generator act as a Synchronous Condenser?

1 Answers  

How many percent of power are not being registered if we bypass one side of the meter base terminal using #8 cu wire on 1-phase kwhr meter. 

1 Answers  

in 132kv substation CRT means

0 Answers  

When should I use earth leakage circuit breaker for incomer and when should I use it for each feeder seperately?

1 Answers  

why in transformer there is not rotating fiddl/ magnetic field like motor

4 Answers