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| substation code |
Higher-Level Designation: Item designation for any major part of Bay or Feeder
Example: B10
66KV Bay Number 01
Location of Item:
This block is composed of two items
ANN= Indicates which part belong the equipment
AANN= Indicates equipment which contains the item
Example: +C10.AX10
Disconnecting switch box- bay 132KV Number 01
Identification of
Item:
Example: -K01 Auxiliary Relay Number 01
Substation Voltage
Level Indicate by Letters
|
Letters
|
Voltage Level
|
Color Code
|
|
A
B
C
D
E
G
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11KV
66KV
132KV
220KV
33KV
400KV
|
Red
Brown
Black
Blue
Green
Pink
|
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| substation protection board |
|
Code
|
Designation
|
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AA
|
Control Board
|
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AB
|
Protection Relay Board
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AF
|
Local Control Cubicle
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AG
|
Current Box
|
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AH
|
Voltage Box
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AK
|
Interfacing Telecontrol Cubicle
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AL
|
Remote Terminal Unit
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AM
|
Transformer Auxiliary Cubicle
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AN
|
On Load Tap Changer Cubicle
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AP
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Telecommunication Panel
|
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AQ
|
Tx. Auto Voltage Regulation
|
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AW
|
Circuit Breaker Cubicle Box
|
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AX
|
Disconnecting Switch Box
|
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AY
|
Pilot Wire Box
|
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BB
|
Pilot Wire Terminal Box
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| substation relay number |
|
Relay Code
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Designation
|
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F21
|
Distance Protection
|
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F27
|
Under Voltage Protection
|
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F27T
|
Wiring Supervision Relay
|
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F49
|
Thermal Overload Protection
|
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F50
|
Instantaneous Over Current Protection
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F50BF
|
CB Failure Relay
|
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F50N
|
Instantaneous Earth Fault Protection
|
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F51
|
Delay Time Over Current Protection
|
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F51N
|
Delay Time Over Current Protection
|
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F59
|
Over Voltage Protection
|
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F62
|
Timing Relay
|
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F63G
|
Fluid Pressure Level or Flow Relay
|
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F63B
|
Buchholz
|
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F67
|
Directional Over Current Protection
|
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F67N
|
Directional Ground Fault Protection
|
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F76
|
DC Overcurrent Protection
|
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F86
|
Lockout Relay
|
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F87B
|
Busbar Differential Protection
|
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F87L
|
Line Differential Protection
|
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F87PW
|
Pilot Wire Differential Protection
|
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F87T
|
Transformer Differential Protection
|
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F87N
|
Restricted Earth Fault Protection
|
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F87BM
|
Busbers Differential Protection (Main)
|
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F87BCH
|
Busber Differential Protection (Check Zone)
|
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F90
|
Voltage Regulator Relay
|
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F91
|
Voltage Directional Protection
|
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F94
|
Self Reset Relay
|
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F96PW
|
Pilot Wire Supervisory Relay
|
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F96TW
|
CT Wiring Supervisory Relay
|
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F97
|
Fire Protection
|
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F5050PN
|
Instantaneous/ Delay Time Phase & EF Realy
|
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F6767N
|
Directional Phase Ground Fault Protection
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