Answer / afrooz

NGR means neutral grounding resistor.It is used to limit
the earth fault current.

Answer / vijay kumar

NGR(Neutral Ground Resistor) which is connected at the star
point of an alternator or a tranformer..
There two consideration to Select NGR
1) Plant capacity
2) Current carrieng capacity
If any unbalance current occures in any of the phases
that surplus current will alowed to flow through the NGR,
where in Neutral current will suuprssed so that alternator
winding will be in safe,

Answer / mahesh sali

NGR is neutral grounding resistor , 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 with w.r.t neutral .

generally the NGR earthing used upto the 11kv , Ac sply.

Answer / subhakant / bhajahari

NGR MEANS NEUTRAL GROUNDING WITH RESISTANCE. THE PURPOSE OF
USING NGR FOR NEUTRAL GROUNDING IS TO LIMIT THE FAULT
CURRENT WITHIN THE OPERATING RANGE OF PROTECTING EQUIPMENTS
AND ALSO TO SENSE THE SYSTEM UNBALANCE CURRENT

Answer / sandeep pareek

N.G.R. USE TO ALTERNATOR WINDING PROTECTON WHEN ANY FAUL
OCCURE IN ALTERNATOR N.G.R PROTECT TO ALTERNATOR
WE ARE USE C.T. IN N.G.R. PANEL .. ALTERNATO OUTPUT PHASE
CONNECTION IN STAR THEN FAULT CONDITION EXTRA CURRENT
GROUND AND OUR ALTERNATOR ALSO SAFE

Answer / dibyaranjan pati

NGRs are employed in AC Distribution Networks.It limits the
Restricted Earth Current to a safe value which flows from
the Transformer or Generator star point when an earth fault
occurs in the system without exceeding specified temperature
limits.
Theses are connected between the neutral point of
transformer or generator & the earth.

Answer / abhishek anshu

Main purpose of NGR is :

1. To protect equipment from earth fault.

2. To ground excessive leakage current.

Answer / pps

NGR means neutral ground reactor. Normally it is used in
Generation stations and long line shunt reactors. Main
purpose is to limit fault current when earth faults. and
also it acts as a phase winding when one of the reactor
winding or generetor winding or phese in lines open or
grounded.

Answer / soumen

NGR (Neutral Grounding Resistors )is employed in AC
distribution networks to limit the fault current which
would flow from the transformer or generator neutral star
point in the event of an earth fault in the systems. It is
used when the neutral of supply transformer is accessible
and its own impedance is not enough to limit fault current.
The rating of the protection relays within the required
time.
For Grounding Neutral of Transformer or Generator,
Resistors upto 33 KV are offered for fault of short
duration like 10 sec., 30 sec., 60 sec., continuous etc.

Answer / pramod verma

NGR means nutral ground gearthing. the maine purpose of
this equipment is that when ever fault occur in the
generator or transformer then it limt the fault current for
prevention from any major accident or flow any inbalance
current in normal condition. It always connect with star
point of generator or transformer.

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