Measurement principle.
The test performs the following current injection:
Ih =
Iref
➝
I
ds
+ 10% or set manually
➝
high value.
Il =
Depending on the type of test selected:
80% of Iref
➝
low value. (80% of Iref
≅
90% I
ds
.)
-or-
50% of Iref
➝
low value. (50% of Iref
≅
60% I
ds
.)
t0
➝
t1 =
The rising slope to Il during 210 ms.
t1
➝
t2 =
Current is held constant during 40 ms.
t2 =
At this point, the current rises to Ih as fast as is available
to the BALTO System.
t2
➝
t3 =
The measured opening time.
t4 =
Time limit of the measurement
➝
450 ms.
When entering the Iref value manually, ensure that the I
ds
value is somewhere between Il and Ih. Otherwise, the High-
speed DC Circuit Breaker may not trip, or may trip too soon.
Result:
If the measured trip falls outside of the range t2
➝
t4, (200ms) the measurement is considered invalid.
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Operation