Answer Posted / kunal singh dabi

Resistance Grounding falls into two categories: Low
Resistance and High Resistance

1) In Low Resistance Grounded (LRG) Systems the current is
limited to 25 amps or more. Generally the range is from 25
to 600 amps, although in some systems it may be even
greater.
2) In High Resistance Grounded (HRG) Systems the current
is limited to 10 amps or less.
------------
A) On systems with a voltage of 1000 volts or less (phase-
to-phase) grounding resistors are not used. Normally these
system use a solidly grounded configuration with no
intentional impedance being introduced into the system.
B) Resistance Grounding is recommended on Medium Voltage
Systems from 1000 volts to 15,000 volts phase-tophase.
C) Because of the cost, Resistance Grounding is not usually
used on systems above 15,000 volts phase-to-phase.
Additionally, the use of a solidly grounded system allows
for use of equipment which is insulated for the
phase-to-neutral voltage of the system.
·D) When a system has protective relays which will trip the
circuit if a ground fault occurs, a grounding resistor with
a 10 Second Rating is often specified, because the relays
will trip the system in less than 10 seconds.However, One
Minute or Ten Minute ratings are sometimes used for an
extra margin of safety, even though the cost will be
greater.

What is electrical cable termination

2634

---

How we calculat the NGR of 3phase Generator, Our generation voltage 11KV

3311

---

What is meant by time harmonics and space harmonics?

2807

---

Load break swicth maintenance procedure.

1777

---

How to calculate no of Lighning arrestors are required for protecting 50mX 50m*20m cubical building and locations of LA?

1841

---

please explain to me how to calculate current,voltage,resistance with formula??

1439

---

Hi guys! Plz help me to answer the following questions. 1. What are the types of transmission line energy losses? 2. Why are the VLF are used some types of services? 3. What frequencies are used for reliable beyond the horizon terrestrial communication without repeaters? 4. To permit selection of 1 out 16 equi-probable, what is the number of bitis required? 5. What is the most common modulation used for telegraphy? 6. What is the multiplexing is used to increase the capacity of the optic fiber? Thanks

2091

---

what ispositive, negative, zero sequence impedence?

2037

---

what is difference between 2 pole structure and 4 pole structure in transformer yard

6066

---

Why control of DC motor is simpler?

2442

---

it is possible to rotate the DG engine dc starter with wrong polarity connections? why?

2262

---

what are safety measures in /control in diesal engine/ explain them?

1794

---

can anyone tell me can the electromagnetic waves can be reflected back?if so how &by which material it can be reflected back?please tell me so that it can help to my wireless power trasnmission device.

1815

---

what is the Earth Voltages in Power Plants, Sub-stations, Industries, Residential & Commercial Buildings.

2106

---

I WANT TO know WHICH WAY IS BETTER FOR CONNECTION BETWEEN POWER TRANSFORMER AND MAIN DISTRIBUTION PANEL. 1-IS BETTER WE USE CABLE? 2-IS BETTER WE USE BUS DUCT? my transformer rate power is 2500KVA

3256

---