Answer / 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.

Answer / the_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-to phase.

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.

Answer / john

HRG - High resistance grounded.
LRG - Low resistance grounded

why the capacitors works on ac only

5 Answers  

---

why dc motor is called constant flux motor?

1 Answers  

---

Brief function of stepper motor

1 Answers  

---

Why the standard of ambient teperature mentioned as 40 degree celcius in machines.

0 Answers  

---

if negative of DC supply used and positive is grounded through EGB, and if ELCB used in the system then is it sense the positive volatge and get tripped is it possible?

0 Answers   Delta,

---

two transformer connected in parallel.tap change are different.if i want to on the buscoupler what happen?

1 Answers   Essar,

---

Can you used moeller lzm1 mccb in a dc system with 125vdc and 20ka short circuit current , beside is it have 24 or 48 volt shunt ? Beside how long current can through from An MCB shunt contacts? (like Z7-AS 24 V)?

0 Answers  

---

main difference between ac and dc?

0 Answers   Classic Network,

---

what is the formula to calculate the fault level current for any substation?

2 Answers  

---

what is at/cm ?

3 Answers  

---

what is the reactance,capacitance & impedence electrical armoured & unarmored Cables.

0 Answers  

---

a power supply to be constructed from voltage cells is required to provide Max. 20A Current with a terminal voltage of 6v.Several voltage cells are available each of which has terminal voltage of 1.5V & each of which can supply a max current of 5A .the no of cells required will be ??

5 Answers  

---