Iref =
The reference point of the measurement interval.
For an Iref of 2,500 A, ‘K1’ of 97% and ‘K2’ of 103%, the values would become:
t1 =
1,000 ms.
k1 =
97% of I_ref = 2,425 A.
k2 =
103% of I_ref = 2,575 A.
t3 =
t1 + measurement interval at 200 A/s + 40 = 1,790 ms.
A trip occurring outside of the assigned measurement interval (before point e) will be considered invalid.
If the trip occurs before point e, the new Iref value will be the value at which the breaker tripped.
The following screens will be displayed when the trip occurs before point e :
When selecting the graph-button, the following screen will be displayed :
Perform a new AUTO-test, with the new I_ref value, until the breaker trips in the 200A/s interval.
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Operation
