Answer / vinodh.t

fallowing protection are used for alternator
1.differential
2.negative phase sequence
3.over voltage
4.over current
5.thermal overload
6.under frequency
7.earth fault
8.over fluxing
9.over frequency,etc
feeder protection
1.over current
2.earth fault
transmission protection
1.over current
2.earth fault

Answer / anil kumar

Protection for alternator are

Over voltage relay
under voltage relay
Earth fault relay
Over current relay
overload relay
reverse power relay

Answer / amit khamesra

GENERATOR:
Directional O/C & E/F,
Differential
Voltage dependant O/C
NPS
Reverse Power
Low fwd power
O/C
E/F
Standy By E/F
V/F
100 % Stator EF
Over Freq
Under Freq
Over Vtg
Under Freq
Rotor EF

TRANSMISSION SYSTEM
Distance Prot.
Local Breaker Bkp
Pole discrepancy
O/C
E/F

FEEDER PROT.

O/C
E/F
Directinal O/C & E/F

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