Assuming that the High-speed DC Circuit Breaker performs normally in the Quicktest Mode, the Auto Mode injection
may not be reaching the trip level. In this case, adjust the measurement interval manually by increasing ‘Iref’ or ‘K2’.
Alternatively, it could mean that the main circuit or the over-current release of the High-speed DC Circuit Breaker
malfunctioned.
9.10.3 Manual Mode.
In the ‘Selection Testmode’ dialog, press ‘MAN’ to open Manual Mode.
The following menu is displayed:
The menu contains the following tests:
Opening Time Test.
DC Protection Relay Test.
Shunt Mode.
Reaction Time Tests (if supported by the system).
9.10.3.1 Opening Time Test.
This test determines the mechanical response time of the High-speed DC Circuit Breaker.
The mechanical response time is only part of the total electrical interruption time during a real overcurrent event, as
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