
CHAPTER 7: PROTECTION
CONTROL ELEMENTS
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
325
single-pole tripping applications when evolving faults are of importance and slightly
delayed operation on evolving faults could be traded for enhanced accuracy of single-
pole tripping.
Trip Delay on Evolving Faults
Range: 0 to 65.535 seconds in steps of 0.001
Default: 0.000 seconds
This setting should be used in conjunction with the
Reverse Fault
setting (see above). This
value should typically be set around one-half a power system cycle. This setting should
be used only in single-pole tripping applications when evolving faults are of importance
and slightly delayed operation on evolving faults could be traded for enhanced accuracy
of single-pole tripping.
Breaker Phase A Open, Breaker Phase B Open, Breaker Phase C Open
Range: any FlexLogic™ operand or shared operand
Default: OFF
Protection elements are assigned to the trip output scheme will assert appropriate
outputs (the
TRIP PHASE A
,
TRIP PHASE B
,
TRIP PHASE C
,
TRIP 1-POLE
, and
TRIP 3-POLE
operands)
based on the mode setting and the fault type. These outputs are latched until the
D90
Plus
detects the breaker has opened via the open pole logic. A user-defined signal
may also be assigned with these settings to reset the outputs.
Events
Range: Enabled, Disabled
Default: Disabled
This setting enables and disables the logging of trip output events in the sequence of
events recorder.
The trip output scheme logic is shown below.