GE D60 Instruction Manual page 544

CONTROL ELEMENTS
5.8.14.7 Directional comparison blocking 1
SETTINGS  CONTROL ELEMENTS  PILOT SCHEMES  BLOCKING1 SCHEME
 BLOCKING1 SCHEME

5
The Directional Comparison Blocking1 (DCB1) scheme operates the same way as the Directional Comparison Blocking
(DCB) scheme, except hard-coded connections to phase and ground distance elements are removed to allow the user to
choose FlexLogic operands to identify forward or reverse direction fault, such as ground OC directional elements for
example. This gives the user more flexibility and better coordination when employing this scheme.
Settings description and application guidance for DCB scheme apply to DCB1 scheme with the following exceptions.
BLK1 SCHME DIR FWD1-3
on the protected line, and thus, for initiating operation of the scheme. Good directional integrity is the key requirement for
an over-reaching forward-looking protection element.
5-366
BLOCKING1 SCHEME

FUNCTION: Disabled
BLOCK1 SCHEME BLOCK:

Off
BLOCK1 RX CO-ORD PKP

DELAY: 0.010 s
TRANS BLOCK1 PICKUP

DELAY: 0.030 s
TRANS BLOCK1 RESET

DELAY: 0.090 s
BLOCK1 SCHEME SEAL-

IN DELAY: 0.010 s
BLK1 SCHME DIR FWD1:

Off
BLK1 SCHME DIR FWD3:

Off
BLK1 SCHME DIR REV1:

Off
BLK1 SCHME DIR REV3:

Off
BLK1 FORCE TX STOP1:

Off
BLK1 FORCE TX STOP2:

Off
BLOCK1 SCHEME NO OF

COMM BITS: 1
BLOCK1 SCHEME RX1:

Off
BLOCK1 SCHEME RX4:

Off
BLOCK1 SCHEME

TARGET: Self-Reset
BLOCK1 SCHEME

EVENTS: Disabled
— Each setting defines the FlexLogic operand of a protection element for identifying forward faults
Range: Disabled, Enabled
Range: FlexLogic operand
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: 0.000 to 65.535 s in steps of 0.001
Range: FlexLogic operand

Range: FlexLogic operand
Range: FlexLogic operand

Range: FlexLogic operand
Range: FlexLogic operand
Range: FlexLogic operand
Range: 1, 2, or 4
Range: FlexLogic operand

Range: FlexLogic operand
Range: Self-Reset, Latched, Disabled
Range: Disabled, Enabled
D60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS