What should be the minimum and maximum ohmic value for earthing?

What should be the minimum and maximum ohmic value for
earthing?

Question Posted / jagan

2 Answers
6140 Views
I also Faced
E-Mail Answers

Answers were Sorted based on User's Feedback

What should be the minimum and maximum ohmic value for earthing? ..

Answer / p.r.gowri sankar

Earthing Resistance between the phase to earth is must be
below the value is 0.5ohms.

Is This Answer Correct ?

4 Yes

2 No

What should be the minimum and maximum ohmic value for earthing? ..

Answer / engr. rohail joses

Normally the Earthing Resistance value while designing Earthing Systems for Power Plants is kept below 1 Ohm, this value ensures Step and Touch Voltages not acceding their safety limits.Also the GPR (Ground Potential Rise) during Lightning Discharge, Line to Line and Line to ground Faults for less than 1 Ohm Earthing Resistance is also confined within its safe limits and Earthing System is with less than 1 Ohm Earth Resistance becomes fully capable to dissipate/ handle this Destructive phenomenon. This is as per IEEE Standard [IEEE Std 80-2000]. However for small substations and Industries Earthing Resistance value of less than 5 Ohm is also acceptable.

Is This Answer Correct ?

0 Yes

0 No

Post New Answer

More Electrical Engineering Interview Questions

How to calculate cable sizes in sq.mm. with using motor KW? Any formula there?

18 Answers Aswani Properties, BRB Cable, Construction, Hitachi, L&T, Microcool Systems, Nahar, NWPF, Reliance, Renault, Saha Bright Polytech, SGH, TATA, Techno Electric and Engineering, TFIL, Thermax,