What should be the earthing resistance of an industrial
substation and also What should be the house hold earthing
resistance?

Answer Posted / manoj mahajan

The Earthing Resistance of a household should not be
greater than 5-Ohm. This is in keeping with the Indian
Stadards, so also the international standards, viz, IEEE
(Institution of Electrical & Electronic Engineers) and IEC
(International Electrotechnical Commission) which stipulate
that no Earthing Resistance shall be greater than 5-Ohm.
The restriction is required to ensure the safety of the
occupants and the electrical appliances.
The Earthing Resistance of a Power Station should not be
greater than 0.5-Ohm because a Power Station is required to
carry high earth currents.
The Earthing Resistance of a Major Substation such as
a "Receiving Station" or a 400kV/220kV/110kV/66kV etc
Transmission or Stepping Up/Down Substations should not be
greater than 1-Ohm.
The Earthing Resistance of a Minor Substation such as an
11kV/230V Distribution Substation should not be greater
than 2-Ohm.
This clarifies my first answer.

Is This Answer Correct ?    104 Yes 6 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

we have 3 single phase transformers. how will we generate 6 supply from 3 phase supply input

1653


how to select battery for 15 KVA UPS with formula

2084


sir my exam is on 19/6/2013 under electrical branch pls send me sample aptitude questions as well as sample technical questions for jindal steel and power company

1748


How would you relate your key competencies to this position?

1745


can u tell me the promotion from oiller to enginer

1422






difference between Ac and Dc mcb ????

1123


Define ohm’s law for a.c (alternating current)?

625


HOW TO CALCULATE THE HEAT AND LOAD OF LT-SUBSTATION WHICH CONTAINS 2*1MVA TRANSFORMERS,LT SWITCH BOARD,MLDB,ACB,BUSBAR,ETC...?

3483


what is basic difference betmeen normal & flame proof motor??

1625


Why increase in current leads to increase in conductor temperature?

652


Dg pf .71 i am improve pf 0.80 what capacitor connected in dg how?

1241


how is working bearing heater?

1557


what is deffrence between squirral cage and wound rotor in IM?

1529


How to calculate multiplying factor of dc energy meter

1204


what will happen if i connect 12 volt battery with 24 volt battery charger.

1461