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Protection Codes.

2 Time-Delay Starting Or Closing Relay

8 Control Power Disconnecting Device

12 Over-Speed Protection

21 Distance Relay24 Over-Excitation (V!"#

25 Sync$roni"ing Or Sync$ronism C$ec%

26 &ac$ine 'ield Over temperatre SP&

27   )nder voltage Device

27 &ac$ine 'ield )nder voltage Device SP&

27TN T$ird !armonic *etral )nder voltage

30 +nnnciation Relay !++, &ltinction Relays

32   Directional Power Device

37 )ndercrrent37 &ac$ine 'ield )ndercrrent Device SP&

38 earing Over temperatre

40 /oss O 'ield Or Excitation Device (0mpedance#

40Q   /oss O 'ield Or Excitation Device (Reactive Power#

46 Reverse-P$ase Or P$ase-alance Crrent Relay

47 P$ase-Se1ence Voltage Relay

48 0ncomplete Se1ence

49

49

Stator Over temperatreT$ermal 0mage Relay

50/27 

0nadvertent 2enerator Energi"ation

50 0nstantaneos Over crrent Or Rate-O-Rise Relay

51 +C Time Over crrent Relay

50/51 instantaneos +nd Time Over crrent Relay

50/51(+)

 

Over crrent Relay System

51V Voltage Restraint Over crrent Device

50BF rea%er 'ailre Relay

55 Power 'actor Relay56 'ield +pplication Device SP&I

59 Over voltage Relay

59N *etral Over voltage Device

60 Voltage Or Crrent alance Relay

61 &ac$ine Split P$ase Crrent alance

64 2rond Detector Relay

64TN 3445 Stator 2rond Device

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66 Starts Per !ors

67   +C Directional Over crrent Relay

67_2

68

*egative Se1ence Directional Over crrentloc%ing Relay

69 Circit rea%er Spervision +nd Control Device &OV

74 +larm Relay &ltinction Relays76 DC Over crrent Relay P6C

78 P$ase +ngle &easring Or Ot-O-Step Protective Relay

79 +C Reclosing Relay

81 're1ency Relay

81R Rate o C$ange o 're1ency

84 Transormer Tap C$anger Control Device DTR

85 Carrier Or Pilot-7ire Receiver Relay *++

86 /oc%ot Relay

87 Dierential Protective Relay

87L /ine Crrent Dierential Relay

87T Transormer Dierential System

87S &ac$ine Stator Dierential Protection System

87G 2rond Dierential or Restricted 2rond 'alt

87(+) Dierential Relay System

94 Tripping Or Trip-'ree Relay &ltinction Relays

95 SP& Relctance Tor1e Sync$roc$ec%

96 +to loading Relay SP&