Appendix B - Settings and Signals
ORDINAL SIGNAL NAME ELEMENT NAME
DESCRIPTION
VT supervision slow block - blocks elements which would otherwise maloperate some time after a fuse failure event occurs
Three phase output from circuit breaker failure logic, stage 1
Three phase output from circuit breaker failure logic, stage 2
Control trip - operator trip instruction to the circuit breaker, via menu, or SCADA. (Does not operate for protection element trips)
Control close command to the circuit breaker. Operates for a manual close command (menu, SCADA), and additionally is driven by the auto-
reclose close command
DDB_CONTROL_CLOSE_IN_PROGRESS
Control close in progress - the relay has been given an instruction to close the circuit breaker, but the manual close timer delay has not yet
finished timing out
DDB_AR_3_POLE_IN_PROGRESS
Auto Reclose 3 pole in Progress
DDB_AR_1_POLE_IN_PROGRESS
Auto Reclose AR 1 pole in Progress
DDB_AR_SUCCESSFUL_RECLOSE
This signal is set when CB has successfully completed a three phase autoreclose cycle.
DDB_DEAD_TIME_IN_PROGRESS
Three pole dead time in progress
This is a signal issued by the autoreclose logic to the general CB Control logic when the conditions to autoreclose CB are satisfied (dead time
complete, CB healthy etc).
DDB_AR_FORCE_3_POLE_TRIPS
Used by in-built Trip conversion logic to allow AR to convert CB to 3pole tripping
Indicates that AR is in one of the following states, Disabled, Inhibited, AR In Progress or Locked out
Composite lockout alarm - circuit breaker locked out due to auto-recloser, or condition monitoring reasons
DDB to block output contacts, same as setting Commissioning Column -> Test Mode -> Contacts Blocked
Indicates contacts blocked mode enabled. Can be mapped in PSL and sent via InterMiCOM/IM64 to block contacts at the remote end.
A phase undercurrent level detector pickup (detects low current). It is used for breaker failure and for fault record reset.
B phase undercurrent level detector pickup (detects low current). It is used for breaker failure and for fault record reset.
C phase undercurrent level detector pickup (detects low current). It is used for breaker failure and for fault record reset.
SEF undercurrent level detector pickup (detects low current in CT SEF)
Mapped in PSL to all none current protection trip signals to initiate CB Fail
Trip on close functions (either SOTF or TOR) active. These elements are in-service for a period of time following circuit breaker closure