ABB COM600 series User's & Technical Manual page 24

24
COM600 series 5.1
Substation Analytics Technical Manual
•
Immediately after the fault occurrence, the estimate is affected by initial transient
in voltages and currents.
• After one cycle, when the fault has occurred, the fault distance starts to converge
towards the final value.
• After two cycles, when the fault has occurred, the fault distance estimate is ready
and FaultLocator_sc_A can be triggered. The more there is measuring time, the
better the fault distance estimate is.
Figure 4.3-21 The behavior of fault distance estimate in time
The actual trigger time is saved in the registers (recorded data). The trigger method is
defined with the control parameter Calculation Trg mode with the values "External",
"Internal" and "Continuous".
External
In case of external triggering, an external trigger signal should be connected to the TRIGG
input. The trigger signal is typically a trip signal from a protective function. The
TRIGG_OUT output signal can be monitored to see if the distance estimate is updated.
The Pre fault time setting should be set at a default value of 100 ms using the external
1MRS758734
behavior_of_fault_distance_estimate_time.png