Answer / ajay kumar

NGR MEANS NUTRAL GRAUNGING RESISTOR WHICH IS CONNECT TO
STAR POINT OF TF&ALTRNATOR WHICH WORK TO BALANCE THE AXESS
CURRENT IB THE UNBALANCE CONDITION AND ALSO EARTH FALT
ACCURE IN IN MACHINE THR CURRENT SLITLY GROUND THROUGH IT
AND PROTECT THE MACHINE . IT IS USED UP TO 11KV SYSTEM

Answer / vaibhav patil

NGR means neutral grounding resistor.it is use to limit the
foult current in abnormal condition.it have resistor bank
which limit the plant current but not fault current.earth
fault CT is also mount at this for protection against earth
fault.

Answer / tirupathi

ngr improoves stability of alternator when ever fault
current flows through it and it improves steadystate
stability limit for synchronous power transmission

Answer / k. venkateswara sastry

NGR is used in HT generators only. This is to control the earth fault currents occurred in Generator so as to limit the damage of Core of the Generator. If core gets damaged, the total generator gets wasted.Hence it is necessary to limit the damage of core. The damage is basically done due to Earth fault Current. Current is the element  any where in Electrical system to generate heat and over heat damages. 

Answer / avinash kumar

NGR means neutral grounding resistor.It is used to limit
the earth fault current.generally the NGR used upto the 11kv
Ac system.The function of NGR is to protect the equipments
against the earth fault , help to limit the fault current to
earth.Its also give the additional purpose to maintain the
balance current in all three phases w.r.t neutral . Its also
give the additional purpose to maintain the balance voltage
between all three phases w.r.t neutral .

Answer / ajay yadav

N.G.R. IS THE NUTRAL GRAUNDING RESISTENCE WHICH IS
INSTALLED ON THE OUTPUT OF POWER TRAFO. OR ALTERNATORS AS
WELL. IT PROTECT THE TRAFO. OR ALTR. FROM THE FAULTY
CONDITION BY GROUNDING THE ACCESIVE CURRENT DUE FAULT.
IT'S ALSO PROVIDE THE RELIABLE OPRATION IN UNBALANCE
CONDITION by GROUNDING THE UNBALACE PHASE CURRENT.

Answer / er. avijit dixit

NGR means neutral grounding resistors....it is just used for
the purpose of solidly grounding arrangement of star
connected 3.3 kv to more stator winding of alternator. NGR
IS USED WITH A HIGH RESISTANCE FOR ABOUT 65.5 OHMS IN FOUR
PARTS MEANS 63.5*4 IS THE TOTAL VALUE. IT LIMITS THE NEUTRAL
CURRENT UP TO THE SPECIFIED CT RATIO AND ALSO PROVIDES A
DIFFERENTIAL PROTECTION TO THE STATOR WINDINGS OF
ALTERNATOR. NGR IS ALSO USED TO PREVENTS THE EARTH LEAKAGE
STRAY CAPACITANCE AND STOPS THE REVERSE SURGES. IT PROVIDES
PROTECTION TO THE PROTECTIVE CTS AND PTS AGAINST HEAVY
EARTH CURRENT FLOW DURING STABILITY LOOSE.

Answer / subodh jain

NGR stans for neutral ground resistor...
it is sometimes also called NGT..neutral ground transformer

its purpose is to dissipate extra unbalance current that flows
into any winding in form of heat..rather than just connecting them to ground

Answer / rohit saroha

NGR(Neutral Ground Resistor) which is connected at the star point of an
alternator ... N.G.R PROTECT TO ALTERNATOR WE ARE USE C.T. IN N.G.R.

Answer / yogesh patil

neutral grounding resistor is used for the protection of
transformers , alternators & other costly equipments in the
system, when any fault occurs in the system , system
becomes unbalanced, NGR limits the fault current to give
the enough time to the protection circuit to operate

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