CHAPTER 7: PROTECTION
CONTROL ELEMENTS
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
355
Incomplete Sequence Time
Range: 0 to 655.35 seconds in steps of 0.01
Range: 5.00 seconds
This setting specifies the maximum time interval allowed for a single reclose shot. It is
started whenever a reclosure is initiated and is active until the
CLOSE BKR1
or
CLOSE BKR2
signal is sent. If all conditions allowing a breaker closure are not satisfied when this time
expires, the scheme goes to lockout. The minimum permissible setting is established by
the
3-Pole Dead Time 2
timer setting. Settings beyond this will determine the wait time
for the breaker to open so that the reclose cycle can continue and/or for the
Pause
signal to reset and allow the reclose cycle to continue and/or for the
AR BKR1(2) BLK
signal
to disappear and allow the
AR CLOSE BKR1(2)
signal to be sent.
Block Breaker 2
Range: any FlexLogic™ operand or shared operand
Default: Off
This setting selects an operand that will block the reclose command for breaker 2. This
condition can include breaker low air pressure, reclose in progress on another line (for
the central breaker in a breaker and a half arrangement), or a sum of conditions
combined in FlexLogic™.
Close Time Breaker 2
Range: 0.00 to 655.35 seconds in steps of 0.01
Default: 0.10 seconds
This setting specifies the closing time for breaker 2 from the moment the
CLOSE
command is sent to the moment the contacts are closed.
Transfer 1 to 2
Range: Yes, No
Default: No
This setting establishes how the scheme performs when the breaker closing sequence is
“1-2” and Breaker 1 is blocked. When set to “Yes”, the closing command will be
transferred directly to breaker 2 without waiting for the set transfer time. When set to
“No”, the closing command will be blocked by the
AR BKR1 BLK
signal and the scheme will
be sent to lockout by the incomplete sequence timer.
Transfer 2 to 1
Range: Yes, No
Default: No
This setting establishes how the scheme performs when the breaker closing sequence is
“2-1” and breaker 2 is blocked. When set to “Yes”, the closing command will be
transferred direct to breaker 1 without waiting the transfer time. When set to “No”, the
closing command will be blocked by the
AR BKR2 BLK
signal and the scheme will be sent
to lockout by the incomplete sequence timer.
Breaker 1 Failure Option
Range: Continue, Lockout
Default: Continue
This setting establishes how the scheme performs when the breaker closing sequence is
“1-2” and breaker 1 has failed to close. When set to “Continue”, the closing command will
be transferred to breaker 2 which will continue the reclosing cycle until successful (the
scheme will reset) or unsuccessful (the scheme will go to lockout). When set to “Lockout”
the scheme will go to lockout without attempting to reclose breaker 2.
