Siemens SENTRON 3WA1 Manual page 195

Result
The table shows that in fault case C, the duration of the load on the power distribution
system is reduced by 0.36 s.
This can also be seen in the grading diagram. The diagram on the left shows the grading
times of the power distribution system without the ZSI system.
In the grading diagram on the right-hand side, a significantly shorter tripping time of
circuit breaker -Q1 can be seen for fault case C. The ZSI system brings about this
reduction.
For the example, the delay t
In addition, an example of a ZSI system over seven grading levels is shown in the
Appendix ZSI system over seven grading levels (Page 564). The example shows the
advantages of the 3WA circuit breaker and the possible complexity of a power
distribution system.
3WA1 air circuit breaker
Equipment Manual, 02/2023, 92310000002-06
0.04 s was chosen.
ZSI
2.10 Zone-selective interlocking ZSI
Description
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