Answer / farooq, nafees, hunjra, haral

For residential & small commercial buildings, Earth
resistance(E.R) should below 25 OHms(acceptable).
While, for industrial installations, It should below 1 Ohm
ideally, however, below 5 Ohms are also acceptable.

Answer / mrinmoy boruah

Earth is a large mass and its potential is zero (neither
positive nor negative). When a matter of positive or
negative potential comes in touch with earth it gets
neutralised by supply or absorption of electrons by the
earth. Thus earth is a neutraliser.

An earth conductor connected to a buried earth pipe/plate
acts as carrier of the neutralising electrons. All of this
happens through the soil in contact with the earth pipe/plate.

Similar to current flow through a conductor there is gradual
dissipation of voltage from earthing terminal point(source)
to large mass of earth(Sink) through the soil in contact
with the earthing pipe/plate. There is gradual potential
drop acroos this surrounding soil.

Resistance of this surrounding soil to flow of current is
called as soil resistivity. Lower the resistivity of soil
lower will be the earth resistance and providing better
earthing i.e better drain point of risky high voltage.

Answer / akash

The resistance used for grounding a neutral point to earth
is called earth resistance......

Answer / brd ganesh

The resistive value of earth conductor(or earth
grid) is known as a earth resistence. It can be
mesure by using ohm meter

Answer / maktec66

The Capacity to withstand the overvoltage or capacity upto the
earth withstands its insulation property

In case of a synchronous generator carbon brushes, some brushes expire before the others. Why is so? When all the brushes are installed at the same time, why don't thee expire at the same time?

1 Answers  

---

What is the settings of distance protection relay in 400 kv line

0 Answers   Crompton Greaves,

---

after syncnhronistion how generator speed controlled by grid

3 Answers  

---

how the percentage impedance affect the transformer loading when connected in parallel.?

1 Answers  

---

What are the effects of adding a zero to a system?

0 Answers  

---

---

what r substations?what r there work?why voltages r incresed and then reduced during distribution of power

0 Answers  

---

Why the transformers are rated in KVA. ? in new view.

2 Answers  

---

what is relation of rpm with Power supply? rpm directly Proposational to power ?

2 Answers  

---

if installing the transformer why put the sprit the stone ?

1 Answers  

---

What will happen if the voltage in my house drops from 220V to any lower voltage?

0 Answers  

---

How CT is connected to measure current by changing plug setting , ratio is 300 - 150 / 5 A ?

1 Answers   Ajanta Pharma, Bhel, Cosmo Films, Suzlon,

---

what is distribution board?

0 Answers  

---