Measurement principle.
The test performs a linear injection up to the maximum available current. If the High-speed DC Circuit Breaker is
functioning, and its I
ds
level is within the available current range, it will trip during the slope and interrupt the flowing
current.
t2 =
Time at which the trip occurs.
t3 =
Total injection time (600 - 2,000 ms).
k3 =
Maximum current, which depends on the number of connected DC Current Generators.
40ms =
Sustained current duration for I
ds
in close proximity to the maximum current.
Power Range
Imax
4,000 A
4,000 A
8,000 A
8,000 A
12,000 A
12,000 A
16,000 A
16,000 A
20,000 A
20,000 A
For High-speed DC Circuit Breakers equipped with an inductive shunt (di/dt sensitive), the operator may need to
perform the test at slower rates of rise to determine the actual I
ds
trip level.
If the found trip level in the Quicktest Mode is due to the high rate of current rise, it will not elicit a trip in the Auto
Mode test.
To start the test, press the ‘Start’ button.
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Operation
