what is the earth resistance

Answer Posted / guest

Ra+Rb+Rc=R
Ra=Length/ depth of the ground electrode•Electrode material
- Solid Copper, Stainless steel (High conductivity,
highcorrosion resistance but low strength & high cost)-
Copper clad steel (high strength, high corrosion
resistanceand low cost)
• The diameter of the rod
- Has little effect- Resistance would only decrease by 10%
by double thediameter
(
R
B
) - The contact resistance of the surrounding earthto the
electrode is negligible.(
R
C
)- The resistance of the surrounding body of eartharound the
ground electrode
- depends on soil conditions such as soil resistivity
4

Is This Answer Correct ?    3 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is FM200 Gas??Applications........

1917


WHaT IS THE CONCEPT OF INDUCTION LAMPS IN MODERN LIGHTINGS, and HOW IT WORKS TO EMIT LIGHT ( AS NO ELECTRODES ARE PRESENT ) ?" COULD INDUCTION LAMPS CAUSE INTERFERENCE WITH COMUNICATIONS INTO A STORE USING INDUCTION LIGHTING ? WHAT IS THE BENEFIT OF USING THE LOW FREQENCY INDUCTION LAMP , VERSUS LED , AND VERSUS FLUORESCENT, AND VERSUS ANOTHER KIND OF LIGHTING . THANK yOU MOISES GUINDI

1648


ii) A shunt motor supplied at 230V, runs at 900 rpm when the current is 30A. The resistance of the armature is 0.4 ohms. Calculate the resistance required in series with the armature to reduce the speed to 600 rpm, assuming that the armature current is then 20A. [12]

1858


what is data block in plc ? How the values of data block are written and read by hmi ? what is the difference between function and function block ?

2925


when the time of backcharging the transformer three phases only enough or three phase with neutral is must.from these which one is the best one.

1581






draw singleline diagram of star to delta and dol starters

1790


PLZ EXPLIN ABOUT CLASS PS CLASS CT .WHY THEY R DESINED AND FOR WHAT PURPOSE?WHY OTHER CT CANT BE USED AS PS CLASS CT? EXPLAIN IN SIMPLE LAUNGAGE IF POSSIBLE PLZ GIVE CIRCIT DIAGRAM?EMAIL-RAJ_SINGH_0376@SIFY.COM

1716


What is milivolt dop test in Busducts? What is its significance & procedure to do the test?

1582


LT cable fault chaecking equipment and to find out the distance at what distence it failure . Name and where it is available?

1675


How generator NPS(NEGATIVE PHASE SEQUENCE TEST)TEST WAS DONE? PROCEDURE WITH DETAILS?

1724


Briefing the effects of ASR and ACR of a double closed-loop speed regulating system.

1696


what is the AC Plant and how can do the work with parts and picture tell us 150 Tr

1551


how can calculation ate Amps for cabel. Ex-for 1sqmm wire hou many amps we can draw

1989


11 kg trivevter meter has rating of -/5amps. And pt ratio11000/110v and is connected with 11kv ct/pt unit of cr ratio 75/5amps. And pt ratio of 11000/110v while checking accuracy of meter with HT Accuchek meter what value of PT ratio and CT ratio to be filled in Accuchek meter

1210


What is the abbreviation of NGT panel

1507